PREPARATION ÂHD REACTIONS OF VINYLENE CARBONATE

DISSERTATION

Presented in Partial Fulfillment of the Requirements

for the Degree Doctor of Philosophy in the

Graduate School of The Ohio State

U n iv ersity

By

ROGER WILLIAMS ADDOR, B .S ., M.S,

The Ohio State University 1954

Approved by:

A dviser ACKNOWLEDGMENT

My sincere thanks are due to Professor Melvin S.

Newman who suggested this problem and whose guidance has been an inspiration. I also wish to thank the other members of the chemistry department for their contributions on my behalf during my stay at the

University and the Research Corporation for the grant which supported this work.

V 47995 11

TABLE OF CONTENTS

Page

Acknowledgment ...... i

Introduction ...... 1

Proposed Syntheses of Vlnylene Carbonate ...... 5

Results and Discussion ...... 6

Chlorination of Ethylene Carbonate ..... 6

Vinylene Carbonate from Monochloro- ethylene Carbonate ...... 9

Vinylene Carbonate from Dichloro- ethylene Carbonate ...... 13

Structure Proof ...... 14-

Reactions of Vinylene Carbonate ...... 15

Diels-Alder Reactions ...... 15 Polymerization ...... 22 Addition of Bromine ...... 23

Periodate Oxidation of Cis-bicyclo(2.2.1)- hept-5-ene-2,3-diol ...... 25

Attempted Dehydrochlorination of Dichloro- ethylene Carbonate ...... 24

Attempted Synthesis of Phenylvinylene Carbonate . 24

Friedel-Crafts Reaction with Mono- chloroethylene Carbonate ...... , 25

Reaction of Dichloroethylene Carbonate with Ethylene G lycol...... 25

Chlorination of Propylene Carbonate ...... 26

Experimental Details ...... 27

Chlorination of Ethylene Carbonate ..... 27

Vinylene Carbonate from Monochloro- ethylene Carbonate ...... 31 i l l Page

Use of Tertiary Amines ...... 31 Use of Other Bases...... 34

Vinylene Carbonate from Dichloro­ ethylene Carbonate...... 36

Structure Proof of Vinylene Carbonate ...... 38

Reactions of Vinylene Carbonate ...... 39

Diels-Âlder Reactions...... 39

With 2,3-Uimethylbutadiene...... 40 With Butadiene ...... 43 With Cyclopentadiene ...... 45 With Hexachlorocyclopentadiene ...... 48 With Anthracene...... 50 With F u ran...... 52 With 3;4,3',4'-Tetrahydro-7;7'- dimethyl-l,l*-binaphthyl...... 60

Polymerization ...... 60

Addition of Bromine ...... 63

Periodate Oxidation of Cis-bicyclo(2.2.l)- hept—5*ene—2, 3**diol...... 63

Attempted Dehydrochlorination of Dichloroethylene Carbonate ...... 65

Attempted Synthesis of Phenylvinylene Carbonate...... 66

Friedel-Crafts Reaction with Monochloro- ethylene Carbonate...... 69

Dichloroethylene Carbonate and Ethylene G lycol ...... 70

Chlorination of Propylene Carbonate ...... 71

Summary...... 73

Appendix I ., Infrared Absorption Spectra ...... 76

Appendix II., Freezing Point Curve-Fractionated Vinylene Carbonate ...... 83

Autobiography ...... 84 iv

LIST OP TABLES

Table No, Page

I. Chlorination of Ethylene Carbonate ...... 7

II, Dohydrochlorlnation of Monochloroethylene Carbonate with Tri ethyl amine...... 10

III, Dehydrochlorination of Monochloroethylene Carbonate with Other Bases...... 11

IV, Conditions for Attempted Dehydration of the Furan-Vinylene Carbonate Adduct ...... 59

V, Diels-Alder Reactions of Vinylene Carbonate.. 75

LIST OF FIGURES

F igure No, Page

1, Structure Proof of Diels-Alder Adducts of Vinylene Carbonate ...... 16

2, Apparatus for Chlorination of Ethylene C arbonate ...... 28 - 1 -

INTRODITCTION

The Diels-Alder reaction is used to form six- membered rings from 1,3-diene systems. Maleic anhydride

is the dieneophile most widely used for this reaction.

If aromatisation of the new ring is desirable, dehydro­ genation and decarboxylation are necessary steps,

(Scheme l ) . The d ecarb o x y latio n of the 1 ,2 -d icarb o x y - lic acid may be particularly difficult and afford low y ie ld s .

I A çh I

I

Scheme 1,

For example, a synthesis of coronene involved, in

part, steps as outlined in Scheme 1, (l) In this case

(1) M, S, Newman, J. Am, Chem. Soc., 1683 (1940), - 2 - the decarboxylation was finally effected only under drastic conditions and in very small yield. The diffi­ culty of the decarboxylation step in the coronene synthesis led to a consideration of dienophiles other than maleic anhydride. Such a substitute dienophile should not only be reactive enough to undergo the initial

Diels-Alder reaction, but should also contain func­ tional groups readily removable to form the new aromatic ring. These requirements led to consideration of the previously unreported vinylene carbonate (A). Thus, according to Scheme 2, the vinylene carbonate-diene adduct would first be hydrolyzed to the corresponding cis-diol and then dehydrated either directly or through a derivative such as the acetate or xanthate. The aroma- tization and removal of the undesired functional groups would occur as one step. Furthermore, the vinylene car­ bonate adducts would be of importance in themselves since hydrolysis would complete a synthesis for cis-diols.

I n ?" <_ x Cs ^-xCHOH I vHI Scheme 2, - 3 -

Although vinylene carbonate would possess no dieno- philic activating unsaturation a-p to the double bond as is present in maleic anhydride, the Diels-Alder addi­ tion would be favored by the compact ring structure allowing approach of the diene with a minimum of hind­ rance. Such unactivated straight chain olefins as vinyl acetate and allyl alcohol had previously been shown to undergo the Diels-Alder addition, (1,2)

Vinylene carbonate would be of considerable in te r e s t as a monomer since polym erization and hydroly­ sis would yield a polymer with the repeating units

■(CHOHf. Also, the use of vinylene carbonate as a copoly­ mer, with or without subsequent hydrolysis, would offer a host of new materials.

Although vinylene carbonate was not reported prior to this work, analogous compounds such as 2-imida- zolone (B) and the substituted 2-oxazolones (C) were well known. In 1952, after the work on vinylene car­ bonate had commenced, the sulfur analog (D) of vinylene carbonate was prepared by passing acetylene through molten sulfur. (3) Attempts to prepare D by dehydro-

(1) K, Alder and H. Rickert, Ann., 5A3. 1 (1939).

(2) K. Alder and E, Windemuth, Ber., 21» 1939 (1938).

(3) F. Challenger, E. Mason, E, Holdsworht and R. Emmott, Chem. Soc., 292 (1953). - 4 - genation of the saturated thiocarbonate using mer­ cu ric a c e ta te were u n su cc e ssfu l. The compound did not undergo a Diels-Alder addition to anthracene on refluxing in benzene for three hours, g g i hm' "nh r n ' "o s ' ' s HC = CH R C =C R HC = CH

BCD “ 5—

PROPOSED SYNTHESES OF VINYLENE CARBONATE

At the outset, the following syntheses of vinylene

carbonate were considered;

CHz-Q

X C H -o '

AgOzCCH'O.^^^ ^ AîO^CCH-cr XCH-o'

• CHl-O' CHrO'^°

t I h \ . ^ % % m 6 0 ^ C H -O .

CHz-cr

CIOCCH-Q 'Nak OCNÇH-Q. ^ ^ CHi-o'' z a CH-0 \HxO HîNçH'O. ifüî?; CH%~ O' 2. AgOH

fe. . CHt-O' ^ CW)6° C H i-o '

% r * > — -5 a -

Since the first method, chlorination of ethylene carbonate followed by dehydrochlorination of the monochloro compound, proved successful, the other proposals were not tried. An attempt to prepare phenyl substituted vinylene carbonate from a-hydroxy- acetophenone (Method 7, R=G&Hg) and ethyl chlorofor- mate or phosgene failed. —6—

RESULTS AND DISCUSSION

Chlorination of Ethylene Carbonate

CHz“*0 CHz—O CICH— O

Ethylene carbonate was found to react with chlorine

at elevated temperatures in the presence of ultra­

violet light. Two pure liquids were obtained by frac­

tionation of the reaction mixture. Surprisingly,

analysis showed the lower boiling component (b.p. 91-92°

at 34-35 mm. ) to be presumably dichloro­

ethylene carbonate and the higher boiling material

(b .p , 129-131° a t 31-32 mm.) to be C^H^O^Cl, presum ably

monochlorethylene carbonate (see structure proof p. 14).

Studies designed to ascertain the best conditions

for preparing large quantities of monochloroethylene

carbonate are summarized in Table I. As can be seen,

the optimum temperature was between about 70° and 80°.

The rate of chlorination increased with temperature,

but above about 80° other unidentified chlorinated

materials were formed which made difficult the isolation

of monochlorethylene carbonate by fractionation. In

two untabulated experiments, even with temperatures

above 70®, chlorination proceeded so slowly as to be

impractical of completion. The cause of this inhibi- TABLE I

Chlorination of Ethylene Carbonate (One Equivalent of Chlorine Added per Mole of Ethylene Carbonate)

Rate g, cl/hr./g. % Dichloro- $ Monochloro- % I n te r ­ Run Temp, Time of Ethylene Ethylene E thylene mediate, No, °C Hours Carbonate Carbonate â. Carbonate ^ Cuts

1 45-50 - ,0078 (47)- - 69 27

2 53-59 27 ,014 - 61 27 I 3 60—68 31 .014 11 ^ 69 ^ 12 ^ I 4 65-70 24 .016 5 69 16

5 70-76 - ,019 (70-74) - 15 60 9

6 70-80 - - 13 65 9

7 85-91 - ,024 (89-91) 2 8 39 42

8 120-12 5 - - 23 - 47

â, Based on fractionation at 20-30 mm. through a 10 inch packed column. ^ Calculated as the weight of all intermediate fractions divided by the total weight of chlorine and ethylene carbonate used. 2 Calculated from a portion of the actual chlorination time where tempera­ ture range is shown in parenthesis. d Fractionated through a 30 inch column. —8— tlon was not determined; on subsequent runs the appara­ tus was steam cleaned before use and no further difficulty was encountered.

The very high boiling point ( 248°) of ethylene

carbonate in comparison with its molecular weight (88)

(1 ) undoubtedly makes possible the apparently anomalous

decreasing boiling points in going first to monochloro­

ethylene carbonate (M.W, 123; b.p, 212°) and then to

dichloroethylene carbonate (M.W. 157; b.p. 178^). Since

the closely related compound, dimethyl carbonate, boils

at only 90°, the high boiling point of ethylene carbonate

must be accounted for by its compact ring structure

which fixes the molecules as permanently oriented dipoles

and allows close, orderly association between them. (2)

The introduction of chlorine into the ring not only

changes the direction and decreases the magnitude of

the dipole, but also the size and compactness of the

molecule. Thus, by the time two chlorine atoms have been

introduced into the ring, the boiling point (178°) is

(1 ) Butyrolactone (M.W. 86; b.p, 203°) represents another example of a somewhat similar cyclic compound having a high boiling point for a correspondingly low molecular weight.

(2) The close association of ethylene carbonate molecules is further illustrated by the molecular weight values. 111 and 115, obtained by freezing point measure­ ments in benzene in two separate experiments. —9— no longer high in comparison to molecular weight (157) and is, perhaps fortuitously, about the same as that of the straight chain analog, bis-dichlorodimethyl carbonate (M.W. 159; b.p. 175°). (l)

Vinylene Carbonate from Monochlorethylene Carbonate

- J 1 £ U HCH-O' CH-O

The preparation of vinylene carbonate (1,3-c.ioxol-

2-one) by the dehydrochlorination of monochloroethylene carbonate was tried with six tertiary amines, one basic ion exchange resin, and two non-amine bases. As shown in Tables II and III, triethylamine was the best dehydro-

chlorinating agent and gave the best yield of vinylene

carbonate (72%) when used in 25% excess with ether as

solvent (Run 7).

The quaternisation of monochloroethylene carbonate and triethylamine was considered as a probable side- reaction to the preferred dehydrochlorination. However, when more highly hindered tertiary amines (tri-n-butyl,

N,N-diethylcyclohexyl, tribenzyl) were used, the yields

of vinylene carbonate decreased (Runs 21-26). Of the three more hindered amines, diethylcyclohexylamine gave

(l) Purity 85%. A. Kling, D, Florentin, and E. Jacob, Ann. ch im ., JL4» 189 (1920). Bî3®iL$ggs£a zi'

table I I

Dehydrochlorlnation of Monochloroethylene Carbonate with Triethylamine

Run % Excess Temp, Time % Y ield ' No, Amine Solvent °C Hrs. ene Garb

1 5 Ether 23-27° 50 56 2 2 E th er 25-30 28 days 31 3 2 Ether Reflux 25 59 4 9(deficit) Ether Reflux 26 60 5 2 E ther R eflux 94 59 6 2 E ther R eflux 45 66 I H 7 25 E ther R eflux 40 72 0 8 50 E ther R eflux 47 65 1 9 100 Ether Reflux 40 63 10 2 moist Ether R eflux 35 39 11 0 Acetone R eflux 7 45 12 2 Acetone R eflux 18 58 13 2 Acetonitrile 0° 41 29 14 2 Acetonitrile 25- 3 0° 41 43 15 2 Acetonitrile R eflux 65 51 16 2 Acetonitrile R eflux 107 — 25-300 30 17 2 Benzene Reflux 21 23 18 2 CH3OCH2OH2OCH3 R eflux 11 28 TABLE I I I

Dehydrochlorlnation of Monochlorethylene Carbonate with Other Bases

Run $ Excess Temp Time % Y ield of No, Base Base Solvent °C Vinylene Ci

19 Trime thylamine 2 E ther 25-30° 21 20 Trimethylamine 100 Ether 0 12 - 21 Tri-n-butylamine 0 Ether Reflux 40 10 22 Diethylcyclohexyl 2 E ther 30-33° 160 46 Amine II 23 2 Ether Reflux 90 40 I II H 24 2 Acetonitrile Reflux 29 33 H 25 Tribenzylamine 2 Ether-Benzene Reflux 90 I Benzene Reflux 16 26 Tribenzylam ine 2 Dioxane Reflux 24 — 27 N-methylpiperidine 5 E ther 25-30° 29 — 28 A m berlite IR-4B E ther Reflux 24 —■ 29 A m berlite IR-4B Benzene Rgflux 67 — 30 Potassium 0 t-Butyl 0° 22 t-B utoxide Alcohol 25 1 31 Sodium 0 E ther 27 0.5 — Triphenylmethÿl 32 (I 0 E ther 0° 2

a Basic ion exchange resin, Rohm and Haas Company, Philadelphia, Penna. - ïï. S. Patent No. 2356151. —12 —

the best yield of vinylene carbonate ( 46% - Run 22) while tribenzylamine did not react, (l) On the other

hand, when trimethylamine was used, a quaternary salt

was isolated in 83^ yield and no vinylene carbonate

was obtained (Run 20), Since the basicities of tri­

methylamine (k^ 6,5x10“ ^) (2 ) and trimethylamine

(k^ 5.9x10“'^) (2) differ only by a factor of about ten,

the steric requirement of these dehydrochlorinating

amines must have been the deciding factor in determin­

ing whether dehydrochlorlnation or quaternization would

occur.

The solvents used in the dehydrochlorlnation with

triethylamine were ether, acetone, benzene, acetonitrile

and 1,2-dimethoxyethane, The best yields were obtained

when e th e r was used as so lv en t and the m ixture was

refluxed for about 40 hours. With acetone as solvent,

a 58$ yield of vinylene carbonate was obtained after 18

hours of refluxing (Run 12) while refluxing in aceto­

nitrile for six and one-half hours resulted in a $1%

y ie ld (Run 15), I t should be pointed o u t, however,

that only with ether as solvent was the dehydrochlorlna­

tion studied sufficiently to reasonably assure that the

(1 ) The best conditions for the dehydrochlorlna­ tion with these amines may not have been found,

(2 ) T, S, Moore and T. F, W inm ill, J, Chem. Soc,, iOi, 1635 (1912). -1 3 - optimum conditions for maximum yield were met.

The basic ion exchange resin, Amberlite IR-4B, (l) and the non-amine bases potassium t-butoxide and sodium triphenylmethyl did not yield vinylene carbonate on reaction with monochloroethylene carbonate (Runs 28-32),

A solid material, m.p, 73-74°, isolated in small yield from the reaction with potassium t-butpxide, showed strained ring carbonyl absorption at 5.60Xf(l780 cm“^) and analyzed correctly for 4-t-butoxy-l,3-dioxclan-2- one. Since in another experiment t-butyl alcohol did not add to vinylene carbonate in the presence of potass­ ium t-b u to x id e , th e a c e ta l-c a rb o n a te compound must have been formed by direct substitution of chloride by the t-butoxide ion,

Vinylene Carbonate from Dichloroethylene Carbonate

ClCH-0. _ cio CH-O. I 0=0 ------2------II ^c=o ClCH-0 CH-0

A 29$ yeild of vinylene carbonate was obtained after refluxing dichloroethylene carbonate with zinc dust in a

1,2-diaethoxyethane—benaene solvent. No vinylene carbo­ nate was obtained when elimination of chlorine was

(l) A product of the Rohm and Haas Company, Philadelphia, Penn, U.S. Patent No, 2356151. —14.— attempted using a sodium iodide-acetone system or a magnesium iodide-magnesium-ether system.

Structure Proof

In addition to the analysis, infrared absorption

spectrum, and molar refraction, the structure of viny­ lene carbonate was established by hydrogenation to ethylene carbonate in 76^ yield using a 5% rhodium on alumina catalyst. Further structure proof was obtained by hydrolysis of vinylene carbonate to glycol aldehyde identified as the phenyl osazone.

On the basis of the established structure of viny­ lene carbonate, the C^H^O^Cl compound (the precursor of vinylene carbonate) obtained by chlorination of ethylene carbonate must have been monochloroethylene carbonate

(4-chloro-l,3-dioxolan-2-one). The infrared spectrum and molar refraction were consistent with that expected for monochloroethylene carbonate.

Hydrolysis of the ^compound afforded by the chlorination of ethylene carbonate gave glyoxal yield as the 2,4-dihitrophenylosazone), Furthermore, the compound was converted to vinylene carbonate by e lim in a ­ tion of chlorine and prepared from vinylene carbonate by the addition of chlorine. These facts, in conjunction with the infrared spectrum and the molar refraction, proved th a t the compound was d ic h lo ro e th y le n e -1 5 - carbonate (4-, 5-dichloro-l,3-dloxolan-2-one).

Reactions of Vinylene Carbonate

Diels-Alder Reactions. - Vinylene carbonate proved to be moderately active dienophile. Solid adducts were formed with six dienes. The conditions and yields are summarized in Table V (fold out p. 75 ). The structures of the adducts were first inferred from the analyses and infrared spectra. Except for the hexachlorocyclo­ pentadiene adduct, the adducts were converted to the corresponding glycols from which the structures were established by conversion to known compounds as out­ lined in Figure 1,

With 2,3-dimethylbutadiene, the first diene studied, no reaction occurred below about 140°; the adduct was first isolated when the reaction was carried out at

140- 150° fo r 13 hours in the presence of excess diene

(Run A-4). The best yields (50-60%) were obtained from runs seven through eleven which incorporated consider­ able differences in the time, temperature, and mole ratio variables. The solid adduct (m.p. 58-59°) de­ composed only slightly when heated in a sealed tube at

175° fo r 14 hours (m.p. 50-58° after heating). The equilibrium should therefore have favored adduct forma­ tion. On the other hand, polymerization of 2,3-di­ methylbutadiene seriously competed with the addition -16.

CH,-O'" \ hOH _^^CH3-C^^% hOCOCH3 5 0 0 ^ C H 3 - C ^ ^ \ h OH,-C^^CHOH PyridinTcHg-C^ ^CH0C0CH,'68^ CH,-C ^CH CHg 89% CH. Identified as sulfonamide

H2 o T ^choh PtOa O k CHOH B " I 1 I CH ^CHOH Quant. CHz ^CHOH CHe CHg cis - m.p. 9 8 -99®

CH y CH C^^7 CH CH^\^CH-OH ptOa CHg r^CHOH H» CH;r\ C. Il CHzl #" I CH I CH2 CH / CH-0 H Quant. CHz I^CHOH Quant. ctt / ^CH^ ^CH CH s COgH cis - m.p. 119 - 121®

CrgO?' CHOH D. CHOH Low H COzH cis - m.p. 281-284®

.COgH ^CH ^CH He .CH CH \^C H O H C r t-\ CHOH PtCfe HNOa ç ^ \ Il 0 I I p I I 0 CH / .CHOH Quant. CHe / .CHOH 8 4 % C&/ CH ^CH ^CH ''COgH cis-m.p. 124-126®

STRUCTURE PROOF OF THE DIELS-ALDER ADDUCTS OF VINYLENE CARBONATE

FIGURE I -1 7 - reaction even though an inhibitor, hydroquinoue, was used. When excess 2,3-dimethylbutadiene was used,

Diels-Alder type dimerization constituted a second less important side reaction.

Under conditions comparable to those used for the

2,3-dimethylbutadiene reaction, butadiene yielded 26%

(Run B) and cyclopentadiene 75 to 77% (Run C) (l) of solid adducts with vinylene carbonate. These results are in accord with the observed activities of diene systems when used with other dienophiles. Thus 2,3-dimethyl­ butadiene is more re a c tiv e than b u tad ien e and diene systems in five and six-carbon rings are, by comparison, very reactive, (2) Hexachlorocyclopentadiene (Run D) and anthracene (Run E) gave good yields of adducts, 80 and 88%, respectively,

A small amount of a second product was present in the crude cyclopentadiene adducts. After isolation by r e c r y s t a l l i z a t i o n , a n a ly s is showed the compound to co n tain two moles of cyclo p en tad ien e to one of viny­ lene carbonate. The ability of cyclopentadiene to add to the double bond of primary adducts (as shown) offers the best explanation as to the probable structure of

(1) The cyclopentadiene adduct is presumably the endo isomer; see discussion, p, 19,

(2) H. L. Holmes, Organic Reactions, John Wiley and Sons, Inc>, New York, Vol, IV, p, 89. -1 8 - the second compound (B). Such analogous secondary adducts have been reported from Diels-Alder additions between cyclopentadiene and allyl cyanide, (l) }-,2- dichloroethylene, (l) vinyl chloride, (2) and vinyl acetate. (2) The structure of the secondary vinyl a c e ta te adduct was e s ta b lis h e d by degradation. (2)

c=o

B

The reaction between furan and vinylene carbonate

produced low overall yields (20-35%) of adducts

(Table V, Run F). Of particular interest, however, was

the fact that two isomers of the primary one to one furan

to vinylene carbonate adduct were formed. Thus the

isomer mixture, m.p. 100- 145°, after chromatographic

separation on silicic acid, gave two compounds, m.p.

137.0-137.7° and 148.8-149.6° in a ratio of 1 to 4,

(1) K. Alder and E. Windemuth, Ber., 21, 1939 (1938).

(2) K. Alder and H. Rickert, Ann., $43. 1 (1939)* -1 9 - respectively. After hydrolyzing a sample of the mix­ ture to the corresponding glycol and hydrogenating the double bond, oxidation yielded 84$ of 2,5-tetrahydro- furan dicarboxylic acid. The degradation results in

conjunction with the infrared absorption curves showed that the two isomers were structurally alike. They are undoubtedly the exo and endo m odifications as shown below. Normal addition of cyclic dienes to dieno­ philes usually gives exclusively the endo isomer and exceptions are rare. (1) Furan and maleic anhydride in ether yield the exo adduct while with maleic acid in water the endo adduct is formed. (2) Mixtures of exo and endo isomers occur in the substituted fulvene maleic anhydride adducts. (l)

e x o

As indicated in Table V (Eun F-l) a third compound

(D) was isolated from the reaction between furan and vinylene carbonate. Analysis indicated that D contained

(1) J. A. Norton, Chem. Rev., 21» PP. 498-500 (1942),

(2) R. B. Woodward and H. Baer, J. Am. Chem. S oc., 2Û, 1161 (1948). -2 0 - two moles of furan to one of vinylene carbonate. Hydro­ genation showed the presence of one rapidly hydrogenated double bond and supported the assumption that the second molecule of furan reacted in the Diels-Alder fashion by adding to the double bond of the primary adduct. Such a secondary addition was reported for the reaction of furan with 1,2-dimethylacetylenedicarboxylate (100-107° for 16 hours) although the structure was not proved, (l)

Further evidence, though not conclusive, that the struc­ tu re of D is as shown is provided by the in fra re d spectrum. Exam ination of the curve shows the presence of 18 ab so rp tio n maxima between 5.6 and 1 4 . 2 / f (1780 and

704. cm,“^) each of which agrees, within a maximum deviation of Q,2J4 > with a corresponding maxima in the infrared absorption curves of either or both of the exo and endo prim ary adducts. Furtherm ore, when a sample of the primary adduct was heated with excess furan at 135° for 20 hours, a part of the products showed the same infrared absorption as D. Higher melting mix­ tures of other compounds were also formed, presumably by the continued addition of furan to give structures as

illustrated.

(1 ) 0, Diels and S. Olsen, J. Prakt. Chem,, 156, 285 ( 194.0 ). -2 1 -

'h As mentioned in the introduction, difficulties arose from the use of maleic anhydride as a dieno- phile in a synthesis of coronene. The diene used in the coronene synthesis was 3,A,3^>4-^-tetrahydro-7,7^- dimethyl-l,l^-binapthyl and gave a 73$ yield of adduct when refluxed In xylene with the very reactive maleic anhydride. Included in Table V (G) is a summary of the attempts to bring about addition of this diene to viny­ lene carbonate. However, even under strongly forcing conditions, i.e., 220° for 63 hours, no addition occurred.

Close comparison of the dienophilic activity of vinylene carbonate with other olefins is difficult be­ cause of variations in experimental conditions. Possible polymerization of the dienophiles also complicates com­ parisons. As a rough approximation, however, under

similar conditions, vinylene carbonate (88$ and 77$ adduct yields with anthracene and cyclopentsdiene, respectfully) shows about the same dienophilic activity as allyl chloride (84$ and 74$ adduct yields with anthracene and cyclopentadiene, respectively) (l)

(1) K. Alder and E. Windemuth, Ber., 21, 1939 (1938). —22 — and a greater activity than vinyl acetate (4-0^ and 43% adduct yields with anthracene and cyclopentadiene, re­

spectively). (l)

Polymerization. - Vinylene carbonate was easily converted to clear viscous liquids or tough plastic

solids by heating with small amounts of benzoyl perox­ ide. The solids became hard and brittle after short exposure to air and darkened without melting when heated above 200^. A film of the plastic polymer d eposited from aceto n e, in which i t was so lu b le, showed

strong carbonyl absorption at 5.55x^(1800 cm,“^). The polymer, insoluble in water, slowly dissolved in solu­ tions of sodium, potassium, or ammonium hydroxide.

Infrared examination of gelatinous solids which pre­

cipitated from a potassium hydroxide solution saturated with the polymer showed hydroxyl group absorption at

(3320 cm."l) and a lack of absorption in the cyclic

carbonate carbonyl range. There is little doubt that the carbonate polymer and the hydrolyzed product have

the structures shown.

O r ^ O H " _ ? ? —CH-CHJ

(1) K. Alder and H. Kiokert, Ann., 542, 1 (1939). “23“

A sample of the polymer dissolved in concentrated ammonium hydroxide yielded, after removing excess base and ammonium carbonate on a steam bath, a dark solid which showed both hydroxyl (2 .9 -3 .1 /t/) and carbonyl

(5.7-5.8^) absorption in the infrared region. Pre­ sumably, partial hydrolysis had occurred to give a product having both of the structural units shown above.

Addition of Bromine. - Although vinylene carbonate would not add bromine at room temperature, refluxing with bromine in carbon tetrachloride yielded dibromo- ethylene carbonate in 94-^ yield*

Other Experiments.

JPerlQdate. Qjci.datl.pn....o.f_ qig-blcyclo(2.2.1 )hept-5- ene“2,3-dlol (A). - When the diol (A) was mixed with a

Hc=UfJq,it(No4

B

cold aqueous solution of sodium periodate, a crystalline solid precipitated (B). Since B did not show carbonyl absorption in the infrared spectrum (strong hydroxyl absorption), but formed a 2,4,-dinitrophenyl hydrazone agreeing by analysis with C, the actual structure of

B was probably as shown.

Attempted Dehydrochlorination of Dichloroethylene

Carbonate . - From 25 g. of dichloroethylene carbonate reacted with an excess of triethylamine in ether, 1,3 g. of a liquid was obtained boiling 6° below the starting carbonate. However, th e compound was impure, co n tain in g dichloroethylene carbonate, and not enough was prepared to allow separation by fractionation.

Attempted Synthesis of Phenylvinylene Carbonate. -

Unsuccessful attempts were made to prepare phenylviny­ lene carbonate from phenacyl alcohol (A) and either o 0 o o 0 CéHît^CHjOH+CICOGHs-^CfeHsCCHaOCOGHir -,

o r ® I? 1 t c f r c i ^ ICeHskHzOcci) ethyl chloroformate or phosgene by routes I or II, Im­ pure ethyl phenacyl carbonate (B) was obtained in low yields, but subsequent treatment with sodium triphenyl- methyl failed to give phenylvinylene carbonate. Phosgene did not react with A at room temperature and when re­ fluxed together in chloroform in the presence of triethyl­ amine, a side reaction occurred to produce diethylcarbamyl chloride - presumably as shown below. With phosgene, 0 0 ClCCl + ffCzHgigNGCl + CgHgCl —25— such analogous reactions have been reported with tri- methylamine (l) and with N,K-dialkyl anilines, (2)

Eriedel-Crafts Reaction with Monochloroethylene

Carbonate and Toluene. - Attempts were made to prepare a substituted ethylene carbonate by reacting monochlor- ethylene carbonate with toluene in the presence of aluminum chloride. However, at the temperature (80°) necessary to bring about reaction, carbonate decomposi­ tion apparently occurred resulting in a mixture of unidentified products.

Reaction of Dichloroethylene Carbonate with Ethylene

Glycol. - An attempt to form A by refluxing dichloro- ethylene carbonate with ethylene glycol led instead to

CHiOH qcH-q, .^1 I + 1 CO — CHzOH CICH-O'

, ÇH°'ÇH'°^CH2 g

the previously reported cis and trans isomers of glyoxal- bis-ethylene acetal (B) (3) in 75% y ie ld .

(1) V, A, Rudenko, A. Takubovitch, and T. Nikifor- uva, J. Gen. Chem. (USSR) 12, 2256 (1947. C.A., 12, 4918.

(2) R. P. Lastovski, J, Applied Chem. (USSR) 19. 440 (1946). C.A., 11, 1214. (3) J. BBeseken, F, Tellegen, and P. C. Henriquez, Rec. trav. chi., IQ, 909 (1931). —2 6“

Chlorination of Propylene Carbonate. - Chlorination of propylene carbonate proceeded exothermally in the presence of ultra-violet light with a reaction tempera­ ture 5° to 10° above the bath temperature of 60-70°,

In the only experiment run, addition of one equivalent of chlorine produced a mixture of products boiling over a wide range and no pure component was isolated. —2 7—

EXPERIMENTAL DETAILS

Recrystallizations were carried out using redis­

tilled solvents. The Skellysolve B and Skellysolve C

used were petroleum fractions having boiling ranges of

65-69° and 90-97°, respectively. Melting point deter­ minations for analytical samples are corrected and were

measured with total immersion thermometers calibrated

by the National Bureau of Standards. Elemental analyses

of the compounds were carried out by the Clark Micro-

analytical Laboratory, Urbane, Illinois and by the Gal­

braith Laboratories, Knoxville, Tennessee. The infrared

absorption spectra in Appendix I were measured on a Baird

Associates, Inc., Infrared Recording Spectrophotometer.

Assignments of spectral absorption peaks to various

atomic groupings were made with the aid of tables of

characteristic infrared group frequencies, (l)

(KLorination of Ethylene Carbonate

The chlorination of ethylene carbonate was carried

out in a steam-cleaned vertical cylindrical container

equipped with a gas inlet tube at the bottom, outlet

tube with a condenser at the top, and an evacuated quartz

U-tube containing mercury vapor as a source of ultra­

violet light (Figure 2), A glycerine bath provided heating,

(l) F. A. Miller, Organic Chemistry - An Advanced Treatise, John Wiley and Sons, Inc., New York, Vol. Ill, p. 140 f f . —28-

High voltage connections - Condenser

50 50

Evacuated quartz tube Chlorine containing mercury (u.v. source) inlet tube

Thermometer

Electrically heated glycerol both

Width 8 cm. Length 36 cm.

APPARATUS FOR CHLORINATION OF ETHYLENE CARBONATE

FIGURE 2 -2 9 -

In a typical reaction 103 g. (1.17 mole) of ethylene carbonate was added and the apparatus was tared and set up so that the ethylene carbonate was heated at 70 to 80° with the glycerine bath. The ultraviolet light source was activated by applying a high voltage and chlorine was passed in at such a rate as to keep the liquid

saturated. After passage of chlorine for about 25 hours, the total gain in weight was 39 g. (40 g. r e ­

quired for monochloroethylene carbonate). Fractiona­ tion through a 2 X 25 cm. packed column gave the follow­ ing cu ts:

Cut B,P, °C Pmm, Weight G, Hg'i-

1 87-91 32-33 7 ,7 1,4618 2 91-93 33-34 16,2 1,4607 3 93-129 34-35 10,2 4 129-132 34-35 3 .7 1,4562 5 132-134 34-35 57,3 1.4534 6 134-134 34-35 24.7 1.4538 7 135 34-35 11,2 1,4526

Cuts one and two (23,9 g.; 13%) were mostly di­

chloroe thylene carbonate (4,5-dichloro-l,3-dioxolan-

2-one) while cuts five, six, and seven (92,2 g,j 65%) were monochloroethylene carbonate (4-chloro-l,3-dioxolan-

2-one),

Pure dichloroethylene carbonate obtained by re­ fractionation is a sharp smelling, lacrymatory, colorless liquid (b.p, 78-79° at 19-20 mm, and 178° at 739 mm,; n^^ 1,4610; 1,5900; MRp calcd, (Eisenlohr) for -3 0 -

C3H2O3CI2 : 26.9. Found: 27.2),

Anal. Calcd. for C 3H2O3GI2: C, 22.9, H, 1.3;

01, 45.2. Found: G, 22.9; H, 1.2; 01, 45.3.

Infrared analysis showed prominent absorption at

5. 40>6f ( l 850 cm."l) indicating a strained ring carbonyl function as is present in ethylene carbonate itself.

Although insoluble in water, dichloroethylene carbonate was slowly hydrolized and addition of phenylhydrazine gave glyoxal phenylosazone (m.p. 167-169°) undepressed on mixed melting with an authentic sample (m.p. 168-170°)

(1 ) Likewise, when 1.34 g. of dichloroethylene carbo­ nate was hydrolized in 8 cc. of dilute ammonia, neutrali­ zation of the mixture and addition of excess 2, 4- d i n i t r o - phenylhydrazine reagent yielded 2.52 g. (87.5%) of g ly o x al 2, 4-dinitrophenylosazone, m.p, about 320° w ith decomposition (reported m.p. 330° ) , ( 2)

Pure monochloroethylene carbonate obtained by re­ fractionation of the higher boiling chlorinated ethylene carbonate fractions is a non-lacrymatory liquid of little odor (b.p. 106-107° a t 10-11 mm., 212° a t 735 mm,; n§^ 1.4530; d?5l,5082; MRjj calcd. for O^H^OgCl: 22.0 . Found 22.0, Anal. Oalcd. fo r O^H^O^Cl: 0, 29.4; H, 2 .5 ;

01, 2 9. 0. Found: 0, 29.6; H, 2.5; 01, 29.2.

(1) H. J. H. Fenton and H, Jackson, J. Ohem. Soc., 578 (1899).

(2) S, Glasstone and A. Hickling, ibid. , 820 (1936). —31“

Strong strained ring carbonyl absorption at 5 . -

1830 cm.-l).

Considerable decomposition at room temperature was found to occur over several months time and was quite probably accelerated by the absorption of moisture and subsequent liberation of hydrogen chloride.

When 115 g. (1.31 mole) of ethylene carbonate was chlorinated at 120-125°, the only relatively pure pro­ duct obtained by fractionation was AJ+.g. (22%) of d i­ chloroethylene carbonate. Of the higher boiling products, which should have contained the monochloroethylene 2 5 carbonate (b.p. 106-107° at 10-11 mm.; n^ 1.453),

64 g. were collected as four fractions, b.p, 101-110° at 12-13 mm. with an average ng^ 1.470. Two further fractionations of this material gave a 3.3 g. middle cut (b.p. 95-97° at 9-10 ram.; 1.4756; d^^ 1.5575;

$01 (Mohr Method) after hydrolysis in water, 39.0,

38. 6. Two equally strong absorption peaks in the carbonyl range at 5.55 and 5.70/(). These data indicated that the fraction was still a mixture,

Vinylene Carbonate from Monochloroethylene Carbonate

A. Use of Tertiary Amines. - The best yield of vinylene carbonate was obtained using triethylamine as the dshydrochlorinating agent in the following manner; -3 2 -

To a refluxing mixture of 150.2 g, (1,22 mole) of mono­ chloroethylene carbonate and 150 cc. of dry ether in a

500 cc. three-neck flask equipped with a Hershberg stirrer, condenser, and dropping funnel was added over a four hour period 155 g. (1.53 mole) of freshly frac­ tionated triethylamine. After the mixture was refluxed and stirred an additional 39 hours, the dark solids were collected on a Büchner funnel and washed thoroughly four times with a benzene-ether mixture (dry weight of solids was 170 g. - theoretical for triethylamine hydro­ chloride was 163 g.). (l) After distillation of most of the solvent and excess triethylamine through a short packed column at reduced pressure, distillation of the dark residue from a Glaisen flask gave 67.5 g. of whitè,

solid vinylene carbonate (cold receiver), b.p. 69-72° at 29-30 mm., and 9.0 g. of fairly dark solid, b.p. 72-80° at 29-30 mm. Redistillation of the second fraction gave

8.0 g. of white solid, b.p. 70-73° at 29-30 mm. bringing the total yield of vinylene carbonate to 75.5 g. (71.6%).

Vinylene carbonate was fractionated for analysis (b.p,

76° at 38-39 mm., 162° at 735 mm.; m.p. 22.0° (uncorr. by time-temperature freezing curve - Appendix II); ïïjj^l,4-189; d^^ 1.354-1; MRg calcd. (Eisenlohr) for 16.7.

(l) The infrared curve of the solids showed slight carbonyl absorption at 5.5/t< , but otherwise checked well with the curve for pure triethylamine hydrochloride. “33“

Found: 16.1. Strained ring carbonyl absorption at

5 .I S M - 1830 c m .-l).

Anal. Calcd. for C, 41.9; H, 2,3.

Found: C, 42.1; H, 2,4.

Other amines used in the attempted dehydrochlorina- tion of monochloroethylene carbonate were: trimethyl- amine, tribenzylamine, tri-n-butylamine, N,N-diethyl~ cyclohexylamine, and the basic ion exchange resin

Amberlite IR-4B. Conditions and results are tabulated in Tables II and III, pp. 10 and 11, respectively.

Of special interest was the reaction of trimethyl- amine with monochloroethylene carbonate. After 20,2 g.

(0,165 mole) of monochloroethylene carbonate was mixed with 22 g. (0.37 mole) of trimethylamine in 120 cc. of dry ether at 0° for 12 hours, filtration yielded 19 g.

(83% as G^ji^O^NGl based on reacted chlorocarbonate) of pale brown solids. No gas was evolved during the react­ ion and distillation of the filtrate gave only 4.5 g. of unreacted chlorocarbonate. The water soluble solids

(in solution) were directly titrated (Mohr method) with standard silver nitrate solution (Calcd. for the quater­ nary s a lt C^H^^O^NCl: Cl, 19.5. Found: 19.2. S tra in e d ring carbonyl absorption at 5.4-5.6if- 1850 to 1725 cm,“^).

The compound d eliq u esced a t f a i r l y low r e la tiv e hum idity and was soluble in ethanol and dimethlyformamide and insoluble in benzene, dioxane, and acetonitrile. Heating —34— g sample at 170-180° in a sublimation apparatus yielded a little orange solid soluble in water, but insoluble

in benzene and, therefore, not vinylene carbonate.

B. Use of Other Bases

1. Potassium t-Butoxide. - To 8.0 g. (O.O 65 mole)

of monochlorethylene carbonate and 60 cc. of 50^ t-butyl

alcohol in ether in an ice-cooled three-neck flask was

added dropwise with stirring 50 cc. (0.062 mole) of a

1.23 M solution of potassium t-butoxide in t-butyl al­

cohol. After being mixed for 22 hours at 0°, the still

basic reaction mixture became neutral after removing the

ice bath and stirring for an additional hour at room

temperature. Filtration yielded yellow gummy solids -

partially soluble in acetone and capable of partial

burning (ash gave a positive halogen test). After the

alcohol was vacuum distilled from the filtrate through

a packed column, distillation of the residue gave 1.3 g.

of partially solid material, b.p. 124-128° at 5-6 mm.

and 1.2 g. of an almost completely solid product, b.p.

128-130° at 5-6 mm. One recrystallization of the second

fraction from petroleum ether (65-110°) gave 0.59 g.

of long fine colorless needles, m.p. 74-75°. The solid

was recrystallized again for analysis (m.p. 73.2-74.0°.

Strained ring carbonyl absorption at 5.60//- 1780 cm,”^).

Anal. Calcd. for 4-t-butoxy-l,3-dioxol-2-ione -3 5 -

(C7H12O4.): C, 52.5; H, 7,6. Found: C, 52.6; H, 7.6.

The molecular weight as determined by freezing point measurements in benzene was 188 (theoretical I 6 0).

However, in separate experiments high molecular weights of 111 and 115 were a lso obtained fo r ethylene carbonate

(theoretical 88) (l) The compound could not be is o la te d when 3.6 g. of vinylene carbonate was stirred for 12 hours at room temperature with 30 cc. of dry t-butyl alcohol in which a small piece of potassium had been dis* solved. After neutralization with acetic acid, distilla­ tion yielded only vinylene carbonate ( 2.8 g .) .

2, Sodium Triohenvlmethvl. - Dropwise addition of

100 cc. of 0 . 035M sodium triphenylmethyl in ether 2 ( )

to 4.02 g. ( 0,033 mole) of monochloroethylene carbonate

in 50 cc. of ether over a half hour period produced an exothermic reaction with immediate disappearance of the

deep red color of the base. However, after the solids were collected on a filter, attempted distillation of

the concentrated filtrate yielded no vinylene carbonate.

Triphenylmethane was isolated from the residue by

(1) The freezing points were measured with a Beckman therm om eter. Enough so lu te was used to give a freezing point depression greater than one degree.

(2) W. B. Renfrew, Jr. and C. R. Hauser, Organic Syntheses, John Wiley and Sons, Inc., New York, Coll. Vol. II, p. 607. —36— o crystallization from benzene, m.p. 90-92 (reported m.p. 92, 5° ) . (1 ) After 2,03 g. (O.OI 64. mole) of mono- o chloroethylene carbonate was mixed at 0 with 30 cc.

(0.0105 mole) of the sodium triphenylmethyl solution, distillation of the filtered and concentrated mixture gave only unreacted monochloroethylene carbonate

(0.57 g .) .

Vinylene Carbonate from Dichloroethylene Carbonate

A. With Zinc D u st. - A fter 10.0 g. (O.O64. mole) of dichloroethylene carbonate was refluxed for 12 hours with 15 g. ( 0.23 mete) of zinc dust in 70 cc. of 35%

1,2-dimethoxyethane in benzene, the solids were collected by filtration. The concentrated residue on distillation yielded 1.59 g. (29%) of vinylene carbonate and an equal amount of impure liquid - partially vinylene carbonate.

Acetone was unsatisfactory as a solvent; a low total yield of products resulted which distilled over a wide range.

B. Attempts with Sodium Iodide in Acetone. - Several attempts were made to eliminate chlorine from dichloro­ ethylene carbonate using a sodium iodide - acetone sys­ tem, In one reaction 17.5 g. (0*112 mole) of dichloro­ ethylene carbonate was refluxed 20 hours with 4-0.2 g,

(1 ) A. Kekule and A. Franchimont, Ber., 907 (1872) -3 7 -

(0,268 mole) of sodium iodide in 300 cc. of acetone.

Most of the acetone was replaced from the d ark trown

mixture by distillation through a packed column while

adding 150 cc, of benzene. The filtered benzene solu­

tion was shaken with saturated sodium bisulfite solution

to remove iodine. After concentration, distillation of

the dark residue gave 14,2 g, of the starting chloro­

carbonate - orange in color. An earlier experiment

had been carried out in a similar manner except that an

attempt was made to remove the iodine by passing the

benzene solution through alumina. Although most of the

iodine was removed in this manner, a large amount of

alumina was necessary and most of the reactant was ap­

parently lost. Thus from 15.0 g. of dichloroethylene

carbonate the only product was 5.6 g. of the starting

material. The infrared curve of the reclaimed chloro­

carbonate was the same as that of the starting material,

C, Attempt with Magnesium Iodide - Magnesium in

Ether. - The procedure used in attempting to eliminate

chlorine from dichloroethylene carbonate with magnesium

iodide in ether was analogous to that used to prepare

p-dioxene from 2,3-dichlorodioxane, (l) After 15,7 g,

(0,10 mole) of dichloroethylene carbonate in 75 cc, of

(l) R. K. Summerbell and R. R, Umhoefer, J, Am, Chem, Soc,, 6i, 3016 (1939). -3 8 - dry ether had mixed with an equimolar amount of magnesium iodide and excess magnesium ribbon for 20 hours, the only distillable product was 6,0 g. of the starting chlorocarbonate contaminated with iodine.

Structure Proof of Vinylene Carbonate

A, Hydrogenation. - Freshly distilled vinylene carbonate (3.06 g.) was shaken for 21 hours with hydrogen

(35 p . s . i . ) and 0,201 g , of a 5% rhodium-on-alumina catalyst (Baker) in 25 cc. of dry ethyl acetate. After filtration of the mixture and removal of most of the

solvent through a packed column, distillation of the residue gave 2,37 g, (75.5/^) of ethylene carbonate, b.p, 130-133° at 21-22 mm. The infrared absorption was identical with that of an authentic sample of ethylene

carbonate. Hydrogenation using platinum oxide (Baker) as catalyst yielded only a small trace of ethylene car­ bonate identified by infrared absorption and mixed melting point,

B, Chlorine Addition. - When a slow stream of

chlorine was passed through a capillary tube into 1.50 g,

of vinylene carbonate, a strongly exothermic addition

occurred and occasional cooling was necessary. After

one hour, the previously colorless liquid was yellow

with chlorine and the increase in weight was 1.24 g. -3 9 -

(theoretical 1.24 g.). Partial distillation yielded

1,5 g. of dichloroethylene carbonate (b.p, 85- 88° a t

27-28 mm., n^^ 1 .4 6 2 0 ). The in fra re d curve was identical with that for dichloroethylene carbonate except for the lack of small dips at 9.3 and 9. 8/^ accom­ panying major absorption peaks at 9.15 and 9. 65/4^.

C. Hydrolysis. - One gram of vinylene carbonate was added dropwise (strongly exothermic) to 4 cc. of concentrated ammonia. After neutralization with acid and 24 hours of shaking with excess phenylhydrazine hydrochloride in 15 cc. of water, gummy solids formed which when recrystallized from 80^ methanol gave a small yield of glyoxal phenylosazone as yellow plates, m.p. 167-169°; undepressed by mixed melting with an authentic sample, m.p, 168-170°. (l)

Vinylene carbonate showed fair stability in pure water. After 1.0 g, of vinylene carbonate had stood for four hours dissolved in 10 cc. of distilled water, con­ tinuous ether extraction for 24 hours yielded, by distilla­ tio n , 0.58 g, ( 58%) of the unchanged carbonate.

Reactions of Vinvlene Carbenate.

A, Diels-Alder Reactions. - Vinylene carbonate was

(1 ) H. J. H. Fenton and H. Jackson, J. Chem. Soc,, 576 (1899), —4-0— shown to be thermally stable under the conditions to which it was subjected in the Diels-Alder reactions, A

1.08 g. sample heated 11 hours at 175-195° in a nitrogen- flushed pyrex tube turned only pale brown and on dis­ t i l l a t i o n 1,03 g. {95%) was reclaim ed,

1, With 2f3-Dimethylbutadiene

a. Addition. - Table V (p. 75 ) summarizes the conditions and results for 12 reactions between vinylene carbonate and 2 ,3 -d im eth y lb u tad ien e. In one of the most successful reactions 4,2 9 g, (0.0499 mole) of vinylene carbonate was heated for 15 hours at 175-185° in a nitrogen-flushed pyrex tube with 1,08 g, (0.0133 mole) of freshly distilled 2, 3-dimethylbutadiene, 1.1 g. of dry benzene, and a few milligrams of hydroquinone.

After removal of the reaction products from a layer of thick polymeric material by décantation and rinsing with a little acetone, solvent was distilled, mostly under vacuum, followed by 3,54 g. of vinylene carbonate.

Finally, 1,35 g. (61# based on diene) of the adduct, the cyclic carbonate of cis- 4, 5-dihydroxy-l,2-dimethylcyclo- hexene, was collected as a slightly oily white solid, b ,p , 132- 134° at 2-3 mm. Recrystallization from 10-15 cc, of 10# ether in petroleum ether (30- 60°) gave 1 ,1 g, of crystals (two crops), m,p, 57,5-59.0°, An oily residue from the mother liquor partially solidified when cold and gave an infrared absorption curve almost super- —41— imposable with that of the solid adduct. An analytical sample of the solid adduct, recrystallized twice from

10^ ether in petroleum ether (30- 60°), formed long colorless prisms, m.p, 57.1-57.7°.

Anal. Calcd. for C, 64.3; H, 7.2.

Found: C, 64. 6; H, 7 .4 .

When a sample was heated I4 hours in a sealed tube at 175°, little decomposition was noted; the product remained a white solid, m.p. 50- 58°.

The reaction between vinylene carbonate and excess

2 ,3-dimethylbutadiene (Run 4) produced about 20^ (based on diene) of a liquid, b.p. 104-107° at 30-31 mm.; 2 5 n.jj 1 . 4769. This was probably the dimer of 2,3-dimetliyl^ butadiene (reported b.p. 85° a t 15 mm.j 1 , 4779), (l)

b. Hydrolysis of the Adduct and Structure

Proof. - After 2.63 g. of the adduct (A) was heated for

OH- . o ' J-OH iC c H jc o to

^ 5 0 0 ° CHs-ij'^XoCOCH, CHî-lj^^^i-OCOCH,

(1 ) E. H. Farmer and R. 0. Pitkethley, J. Chem, S o c ,, 11 (1938), ■“4-2— one hour at 75-100° in 10 cc. of 4-0/b sodium hydroxide, neutralization and ether extraction of the mixture gave

2.13 g. (96%) of 4,5-dihydroxy-l,2-dimethylcyclohexene (B), m.p, 80-83°. A sample for analysis, recrystallized twice from carbon tetrachloride, formed small colorless prisms, m.p. 86.6-87.4°.

Anal. Calcd. for GgH^gOg: C, 67.6; H, 9.9.

Found: C, 67.7; H, 9.9.

A 2,02 g, sample of B was acetylated by mixing over­ night with 8 g. of acetic anhydride in 12 g. of pyridine.

After addition of water, extraction of the mixture with ether, and natralization of the ether portion by washing with dilute acid, distillation of the ether concentrate yielded 2,86 g, (89%) of colorless, viscous cis-4,5= diacetoxy-l,2-dimethylcyclohexene (C), b.p, 121-123° a t 3-4 mm.

Anal. Calcd. for C, 63,7; H, 8,0.

Found: C, 64.1; H, 8.2,

From a small syringe, 2,67 g, of C was added drop- wise over a three hour period to the top of a vertical

11 mm. pyrex tube containing a few glass beads at the top and heated at 495-500° over a 60 cm. length in an electric furnace. The pyrolysis products, continually swept through with a slow stream of nitrogen, were col­ lected in an ice-salt cooled side arm test tube. After “4-3- neutralization of the pyrolysis products with sodium carbonate solution and ether extraction, two distilla­

tions of the ether soluble products gave 0,73 g. (68% based on reacted starting material - 0,5 g, being re­

covered) of o-xylene, b,p, 80-82° at 94-95 mm. The

product was identified by the infrared absorption curve and by preparation of the sulfonamide derivative, (l) m,p, 145. 2- 146,0 - undepressed by mixed melting with an

authentic sample, m,p, 144. 8- 145. 6°,

2, With Butadiene

a. Addition. - Heated in a nitrogen-flushed pyrex

tube for 19 hours at 173-175° were 19.3 g. ( 0,224 mole)

of vinylene carbonate, 4.7 g. (0.087 mole) of butadiene,

5,4 g. of benzene, and 0,1 g, of hydroquinone. After

décantation of the reaction mixture from a large amount

of thick polymeric material, the benzene and 16,1 g,

of vinylene carbonate were distilled at reduced pressure

through a small packed column. Distillation of the resi­

due from a small distilling flask gave 3.19 g. (26% based

on butadiene) of the cyclic carbonate of cis-4,5-di­

hydroxy cyclohexene , b.p, 130-133° at 3-4 mm.; m.p, 48-53°.

Kecrystallization from 30% chloroform in Skellysolve B yielded 2,97 g, of crystals in four crops, m,p, 50-53°.

(1 ) E. H. Huntress and S. P. Mulliken, Ident. of Pure Org. Cpds,, Order I, John Wiley and Sons, New York, p. 524. -4 4 - A sample for analysis, recrystallized once from ether

and once from 20% Skellysolve F in ether, formed long,

flat, blunt-ended prisms, m.p. 52. 4—53. 2°.

Anal. Calcd. for Cf^HgO^: C, 60.0; H, 5.8. Found:

C, 59.8; H, 5 .9 .

B. Hydrolysis of the Adduct and Structure

Proof. - A 1.67 g. sample of the adduct (A) was saponi­

fie d by warming fo r th re e hours in 20 cc. of 10^

potassium hydroxide. After Neutralization with acid,

continuous ether extraction of the mixture for 15 hours

OH 6

gave 1.32 g. (97/0 of cis-4-, 5-dihydroxycyclohexene (B),

m.p. 78-80°. Two recrystallizations from 50]^ Skellysolve

B in benzene and two recrystallizations from benzene

gave small irregular plates which were sublimed (60-70°

at 1-2 mm.) for analysis, m.p, 80.3-80.1° with slight

contracting above 75°.

Anal. Calcd, for H, 8.8.

Found: G, 63.3; H, 9.1.

A 0.0934- g. sample of B was reduced in a conven­

tional midro-hydrogenation apparatus using 10 cc. of -4 5 - ethanol as solvent and a small amount of previously reduced platinum oxide (Baker) as catalyst. The re­ duction was essentially complete within 10 minutes, and a fte r 40 minutes the total uptake of hydrogen was

21,2 cc, (theoretical was 20.8 cc.). After filtration, evaporation of the filtrate left 0.095 g. of solids which after two recrystallizations from Skellysolve B gave tiny plates, m.p, 98-99° (reported for cis-1,2- cyclohexanediol, m.p, 99°). (l)

3. With Cyclonentadiene

a. Addition. - In the most simply conducted experi­ ment the following procedure was used. Heated in a nitrogen-flushed pyrex tube for 16 hours at 170-177° were 4.50 g. (0,0523 mole) of freshly distilled viny- lene carbonate, 1,07 g , (0,0l62 mole as monomer) of fractionated dicyclopentadiene, 1 g, of benzene, and a few milligrams of hydroquinone. The dark reaction mix­ ture was transferred to a small distilling flask, and after 2,63 g, of vinylene carbonate was reclaimed, dis­ tillation of the residue yielded 2,17 g. of nearly white solid, b,p, about 150° at 3-4 mm. Recrystallization from 50^ carbon tetrachloride in Skellysolve B gave

1,89 g. (77% based on diene) of the cyclic carbonate of

(l) P, Bedos and A. Ruyer, Gompt, re n d ,, 204, 1350 (1937). —^6— cis-bicyclo(2.2.1)hept-5-ene-2,3-diol, m.p. 107-112°,

In a similar experiment (Table V, C-l) the distilled product when r e c r y s t a lli z e d from 50% petroleum ether

(30-60°) in ether gave a 65^ yield, m.p, 112- 114°, as the first two crops of crystals and 11#, m.p. 106-

109°, as a third crop (total 76#). A sample of the material melting at 112- 114° was r e c r y s ta lliz e d from 50# carbon tetrachloride in Skellysolve B as small colorless needles and plates, m.p, 114.4-115.0°,

Anal. Galcd, for C^IIgO^: C, 63,2; H, 5,3

Found: 0, 63.5; H, 5.3.)

In a third experiment 12.9 g, (0.150 mole) of viny­ lene carbonate was heated 15 hours at 170-175° with

5.30 g. (0.0802 mole as monomer) of dicyclopentadiene and 5 cc. of benzene. After distillation of 12 g. of vinylene carbonate, the residue (12 g,) was recrystall­ ized from water (400 cc,) yielding 10.7 g. of colorless plates in three crops, m.p. 95-110°. Recrystallization from ether - petroleum ether (30-60°) gave 9,3 g. (76#)

of pure adduct, m.p, 113-115°, as four crops. By num­ erous tedious recrystallizations of the solids from the

concentrated ether mother liquor, a few milligrams of

small plates (from Skellysolve B) were obtained, m.p,

162-165° after vacuum sublimation.

Anal, Galcd, for (Table V, structure B) :

0, 71.54; H, 6. 46, Found: G, 71,86; H, 6,07. —ii7—

b. Hydrolysis of the Adduct and Structure

Proof. - After 7.07 g. of the adduct (A) was warmed for r T " ^ O rss CO2 H c one hour w ith 40 cc. of 20% potassium hydroxide, the mixture was neutralized and ether extracted. Recrystal­ lization of the ether concentrate from carbon tetra­ chloride - Skellysolve B gave 5.06 g. (86%) of cis— bicyclo(2.2.l)hept-5-ene-2,3~diol (B), m.p. 173-177°; after sublimation, m.p. 176-179° (brown melts). Further recrystallization and sublimation failed to affect the melting point.

Anal, (sublimed sample) Calcd. for 07^10^2 '

C, 66.6; H, 8.0, Found; C, 66.3; H, 8. 0.

A 0.204 g. sample of B in ethanol was hydrogenated in a conventional micro-hydrogenation apparatus with a small amount of previously reduced platinum oxide (Baker) as c a ta ly s t. The re d u c tio n was m ostly complete w ith in

10 minutes; the total uptake of hydrogen after two hourss was 42.5 cc. (theoretical was 40.9 cc.). After filtra­ tion of the mixture and evaporation of the solvent, —4-8~ recrystallization of the residue from Skellysolve B gave cis-bicyclo(2.2,1.)heptane-2,3-diol (C) as long flat needle aggregates, m.p. 210.6-212,4. - pale brown melt in sealed capillary.

Anal. Calcd. for » 65.6; H, 9.4.

Found: G, 65.5; H, 9.3.

To 0.12 g. of 0 in 2 cc. of water was added 15 cc. of iced oxidizing solution, (l) After standing for one hour at 13-15°, a little concentrated sodium bisulfite solution was added and the mixture was continuously ether extracted for six hours. Evaporation of the ether gave 0.15 g. (100%) of fine colorless crystals, m.p.

119-121° after two recrystallizations from 50% benzene in Skellysolve B (reported for cis-l,3-cyclopentane- dicarboxylic acid, m.p. 120-121.5°). (2) A 0.0325 g. sample required 4.056 cc. of O.lOllN sodium hydroxide - neutralization equivalent 79.2 (theoretical 79.1).

4. With Hexachlorocvclonentadiene. - Heated in a nitrogen-flushed pyrex tube at 177-183° for 26 hours were

13.0 g. (0.151 mole) of vinylene carbonate, 8.2 g.

(0.030 mole) of hexachlorocyclopentadiene (fractionated,

(1 ) Prepared from 4.08 g. of potassium dichromate, 60 cc. of 95^ sulfuric acid, and 120 cc. of water as re­ commended by L. Semichon and M. Flanzy, Gompt. rendu., 254 (1932). (2) F. W. Semmler and K. Bartelt, Ber., 866 (1908). -4 9 - b.p. 82-84° at 3-4 mm.) and 5 g. of benzene. After a little dark amorphous material was collected by filtra­ tion, excess vinylene carbonate (7.9 g.) was removed by vacuum d i s t i l l a t i o n through a sm all column. The brown solid residue was dissolved in 30 cc. of benzene and passed through a small column of alumina. After replace­ ment of most of the benzene with Skellysolve C (30-40 cc.), crystallization yielded 9.29 g. (three batches) of solids, m.p. 130-180°. Recrystallization from Skelly­

solve B (80 cc.) gave 8.62 g. (80% based on diene) of

the cyclic carbonate of cis-l,4>5,6,7,7-hexachlorobicy-

clo (2.2 .1. )hept-5-ene-2 ,3-diol in four crops, m.p. 24O-

243°. A sample for analysis, recrystallized from

Skellysolve B, formed long needles, m.p. 241.0-242,8°

contracting at 236°*

A nal. Calcd. f o r GgHgO^Cl^: 0, 26.8; H, 0.6;

Cl, 59.3. Found: C, 26.6; H, 0.5; Cl, 59.2.

Attempts to convert the hexachlorocyclopentadiene

adduct to the corresponding glycol by using either aque­

ous or alcoholic potassium hydroxide solutions resulted

only in rapid decomposition. Refluxing with excess

ethanol in the presence of a little potassium carbonate

failed to affect the adduct. Refluxing in methanol

with a little hydrochloric acid produced an oil the

s tru c tu re of which was not determ ined. -5 0 -

5. With A nthracene

a. Addition. - Heated in a nitrogen-flushed pyrex tube for 11-12 hours at 160-170° were 0.52 g. (0.0029 mole) of anthracene (recrystallized from benzene), 2.06 g.

(0. 024. mole) of vinylene carbonate, and 4 cc. of dry benzene. On cooling and opening the tube, 0.43 g. of crystalline product was collected by filtration, m.p.

254- 256°. After the solvent and 1,53 g. of vinylene car­ bonate were distilled from the filtrate, the solid resi­ due was recrystallized in the cold from benzene-Skelly- solve B and yielded two crops of crystals (0.25 g.), m.p. 255-257° (total yield of the cyclic carbonate of cis-9,10-dihydr0- 9,10-ethanoanthracene-11,12-diol was

0.68 g. - BB%), A sample for analysis recrystallized from benzene formed tiny colorless needle aggregates, m.p. 259. 0- 259. 6°.

Anal. Calcd. for ‘^ 17^12*^3* 77.2; H, 4.6.

Found; C, 77.3 ; H, 4. 8.

b. Hydrolysis of the Adduct and Structure

Proof. - A 0.28 g. sample of the adduct (A) was converted -5 1 -

OH- HOH :hoh

H COzH to cis-9,10-dihydro-9,10-ethanoanthracene-cis-11,12- diol (B) by warming for one hour with 7 cc. of 4-0% sodium hydroxide. After neutralization with acid and thorough extraction of the mixture with benzene, two recrystallizations of the solid benzene concentrate

(0,28 g.j 100%) from 20^ Skellysolve B in benzene gave colorless needles, m.p. 201,9-202.7°.

Anal. Calcd. for 80.7; H, 5,9.

Found: 0, 80.9; H, 6,0.

A slurry of 0.13 g. of B and 10 cc. of acid di­ chromate solution (see footnote, p. i^.B) was kept at

13-17° for five hours and at 0° for 11 hours. After addition of 10 cc. of saturated salt solution, continu­ ous ether extraction carried over during the first half hour suspended orange material which, when recrystal­ lized from a little benzene - Skellysolve B, gave 5 mg. of yellow plates, m.p, 281-284° (reported for cis-9,10- dihydroanthracene-9,10-dicarboxylic acid, m.p, 283°). (l)

(1) J, Mathieu, Ann., (ll) 20, 215 (1945), -5 2 -

Further ether extraction yielded small amounts of the same a c id ,

6. With Furan

a, Addition. - Table V gives the conditions and results for six reactions between vinylene carbonate and furan. Two experiments are described; the first is the simplest and the second is included to illus­ trate the complexity of the reaction in some cases and procedures used to separate products.

(1). - In the simplest experiment, 4.0 g. (0.059 mole) of furan was heated at 123-127° for 20 hours with

25.0 g. ( 0,29 mole) of vinylene carbonate (mole ratio of vinylene carbonate to furan 5:1) in a nitrogen- flushed pyrex tube. After benzene and 21.8 g. of viny­ lene carbonate were collected by distillation through a small column, distillation of the residue from a small distilling flask yielded 3.09 g. (34%) of solid adduct, b.p. about 150- 165° at 1-2 mm. (considerable dark residue). Reerystallization from benzene and a little

Skellysolve B gave 2.69 g. of small colorless needles, m.p. 95- 140°, which were, as shown in the following experiment, a mixture of two furan - vinylene carbonate adduct isomers.

(2), - A 6.2 g. ( 0,091 mole) sample of freshly distilled furan was heated at 137-143° for 21 hours — 53— w ith 23.4 g . ( 0,272 mole) of vinylene carbonate (mole

ratio of vinylene carbonate to furan 3:1). After 17,8 g,

of vinylene carbonate were reclaimed by distillation,

attempted direct recrystallization of the dark solid

residue was unsuccessful, yielding oil-contaminated

products. The solids when heated with 30 cc. of chloro­

form left, after filtration, 1.16 g. of insoluble grainy

material, m.p. about 260° with decomposition. D istilla­

tion of the chloroform soluble portion, after concentra­

tion, yielded two arbitrary cuts of white solids;

(A) 2.43 g.J b.p. 140-160° at 1-2 mm.; m.p. 95-125°;

and (B) 1,53 g .; mostly sublimed over 200° at 1-2 mm. with bath to 250°; m.p. 190-235°. There were 2,8 g. of

light-brown brittle residue.

Recrystallization of cut A from 15 cc, of benzene -

carbon tetrachloride gave 2.17 g, of needles, m.p.

100- 145°. A 1.0 g. sample of recrystallized product in

50 cc. of benzene was chromatographed on a 3.4 x 16 cm.

column of silicic acid (l) and developed with a mixture

of 720 cc, of benzene, 120 cc. of Skellysolve C, and

55 cc, of ether (6^ of total). After ejection of the

silicic acid column, streaking with permanganate

(1 ) Silicic acid (Milinkrocdt Chromatographic Grade according to the method of L. L. Ramsey and W. J, Patterson) two parts to one part Johns Manville "Celite", —54- solution showed a 4 cm. band one-third from the top of the column and a 2 cm. band at the bottom. Elution of the upper band with ether gave, after concentration,

0.15 g. of solids which were recrystallized from 40/& chloroform in carbon tetrachloride as fine colorless needles, m.p, 137,0-137.7°.

Anal. Calcd. for CyH^O^: C, 54.6; H, 3.9.

Found; 0, 54.5; H, 4.1.

Elution of the bottom part of the column gave only 0.06 g. of solids, but evaporation of the develop­ ing solvents and recrystallization of the residue from

40$ chloroform in carbon tetrachloride yielded 0.72 g. of fine colorless needles, m.p. 148.8-149.6°.

Anal. Calcd. for C^H^O^: C, 54.6; H, 3.9.

Found: C, 54.6; H, 4.1.

The analyses and infrared curves indicated that these two compounds were probably the exo and endo iso­ mers of the cyclic carbonate of cis-oxabicyclo (2 .2 .|)- h e p t-5 -e n e -2 , 3 - d i o l . The chrom atographic work showed that distilled cut A consisted of 16$ (0.15 g. from

0.93 g.) of "low” melting isomer and 84$ (0.78 g. from

0.93 g.) of "high" melting isomer. The total yield of this isomer mixture (cut A plus 0.82 g. from cut B as described below) was 3.25 g. (23$ based on furan). -55-

When high boiling cut B (1.53 g.) was heated with

1Ü cc. of benzene, a 0.16 g. portion did not dissolve, m.p. 234-236°. The cooled benzene solution yielded an­ other 0.12 g. of the same material. Recrystallization of the two solid fractions from 50 cc. of benzene gave tiny needles which were vacuum sublimed for analysis, m.p. 241.8- 242, 2° with bubbling in a sealed capillary.

Ana 1. Calcd. fo r (Table V, structure D):

C, 59.5; H, 4.5. Found: C, 59.7; K, 4. 6. The benzene mother liquor from cut B yielded, after concentration and addition of carbon tetrachloride, 0.82 g. of the primary isomer mixture (m.p. 98-140°) and an additional 0.17 g. of compound D. The 1.16 g. of chloro­ form insoluble material obtained early in the experiment gave an additional 0,29 g. of D by recrystallization from benzene and brought the to ta l yield of this m aterial to 0.74 g. ( 7.4% based on furan). A very small portion of the remaining chloroform and benzene insoluble solids

(0.87 g.) sublimed when heated above 200° at 0.05 mm,

(m.p. about 200-230° with decomposition). The analysis

(C, 59.5; H, 4. 7) agreed with that for D although the infrared absorption curves were only partially similar.

When 0,50 g. ( 0.0032 mole) of the primary furan adduct (m.p. 95-140°) was heated for 20 hours at 135° with 0.88 g. ( 0.0102 mole) of furan, 0,31 g. of benzene -56- soluble and 0,60 g. of benzene insoluble solids were formed. The infrared curve of the benzene soluble mat­ erial, after partial sublimation (m.p. 150-210°), was very similar to that of compound D. The infrared curve of the benzene insoluble solids (m.p. 230-300°) differed considerably from that of D. All of the high melting furan-vinylene carbonate compounds, however, had common strong absorption bands at about 5.6, 8.6,

9.1-9.2, 9.7-9.9, 10.8-11.0, 11.9, 12.6-12.8, and

1 3.0-1 3 .1 ^.

b. Hydrolysis of the Adduct and Structure

Proof. - A 0.23 g. sample of the "high" melting isomer adduct A (m.p. 149°) was shaken for five hours with 5 cc, of 5% sodium hydroxide. After neutralization with acid.

OH’

Co] p d Co»H continuous ether extraction of the mixture foi 50 hours gave 0.19 g. ( 100#) of cis-oxabicyclo(2.2.l)hept-5-ene- -57-

2 ,3-diol (b ), m.p. 145-152°. Two recrystallizations from benzene (small needles) and a partial crystal­ lization from Skellysolve G had little affect on the melting point. A sample was sublimed (100 at 10 mm.) for analysis, m.p. 147-152°.

Ana 1. Calcd. for C^HgO^: G, 56.2; H, 6.3.

Found: G, 56.2; H, 6.6.

After a mixture of the two isomers of A was quan­ tita tiv e ly saponified as above to give the mixed glycol

(B), m.p. 85-122°, a 0.254 g. sample was hydrogenated in ethanol with a small amount of previously reduced platinum oxide (Baker) as catalyst. The reduction was essentially over after 15 minutes; total uptake of hydro­ gen a fte r one hour was 50.9 cc. (th eo retical was 50.2 cc.).

After filtration, evaporation of the solvent gave the mixed saturated glycol (G).

According to a procedure used to oxidize 5-hydroxy- methyl-2-carboxytetrahydrofuran, (l) 0,25 g. of C was mixed with 3 cc. of nitric acid (d 1 . 42) and heated for two hours at 75-80°. The mixture was poured into a small evaporating dish, water was added, and the solution was partially evaporated in a stream of air. After

(l) ¥. N. Haworth, W. G. M. Jones, and L. F. Wiggins, J. Chem. Soc., 1 (1945). “58—

several dilutions and partial evaporations, final

drying yielded 0.26 g. (84%) of small yellow plates, m.p. 124-126° after two recrystallizations from ether -

Skellysolve F (reported for cis-l,3“tetrahydrofuran- dicarboxylic acid, m.p. 126-127°). (l) A 0,0387 g.

sample required 4.056 cc. of 0.1011 ÏÏ sodium hydroxide - neutralization equivalent 80.4 (theoretical 80.1).

c. Attempted Dehydration of the Adduct. - The general procedure followed in attempting to dehydrate the vinylene carbonate - furan adduct was: (l) weigh

out 0.10-0.15 g. and treat with the dehydrating a gent,

(2) n eu tralize, and (3) iso late the products by continu­ ous ether extraction and identify by infrared absorption,

No catechol or its cyclic carbonate was obtained in any

of the experiments as outlined in Table IV.

d. Hydrogenation of Compound D. - A 0.0682 g.

sample of the adduct containing two moles of furan per mole of vinylene carbonate (D) was hydrogenated in acetic anhydride with a small amount of previously re­ duced platinum oxide (Baker) as catalyst. Rapid uptake of hydrogen was complete within 16 minutes (8.0 cc.; theoretical was 7.8 cc.), A further very slow uptake

of hydrogen (12.7 cc. in five days) was possibly

(l) W. N. Haworth, W. G. M. Jones, and L. F. Wiggins, J. Chem. Soc., 1 (1945). -59- TABLE IV

Conditions for Attempted Dehydration of

the Furan Vinylene Carbonate Adduct

Dehydrating Temperature Time $ Adduct Agent °C. Min, Reclaimed

90$ EgSO, 27 60 55

90$ H28O4 55-60 30 100

95$ H2SO4 75-76 17 AO

Acetic Anhy, + Trace HgSO^ 97-100 90 62

Polyphosphoric Acid 95-100 60 88 -60-

attrib u tab le to cleavage of carbonate or endo oxygen

bonds.

7. With 3,4,3^.4^-Tetrahydro-7.7^-dimethyl-l.l^-

binaphthyl . - In five experiments (Table V) conducted

under d ifferen t conditions of time and temperature no

carbonate adduct was detected in the reaction products.

In one experiment, 0.75 g. (0.0025 mole) of the diene was

heated in a sealed tube at 205-210° for 20 hours with

2.3 g. (0.027 mole) of vinylene carbonate. A fter 2.0 g.

of vinylene carbonate was recovered by distillation,

the dark residue (in ether) was passed through alumina

and a little solid was obtained from the elutriate,

m.p. 130- 136° (recrystallized from carbon tetrachloride).

The infrared curve showed no carbonyl absorption and the

material was not investigated further. In an attempt

to bring about possible acid catalysis, the reaction

was repeated in the presence of a little methyl borate

at 180° for 33 hours. After distillation of the viny­

lene carbonate, chromatographic purification of the

residue again made possible the isolation of a crystal­

line product, m.p, 119-121°. The infrared curve again

showed no carbonyl or carbon-oxygen absorption and the

material was not investigated further,

B, Polym erization. - Heating vinÿtlene carbonate

at 100° with small amounts of benzoyl perioxide produced 1 —61— viscous liquid polymers and solid polymers, depending upon the time of hea ting and the amount of catalyst used. When 4.7 g. of freshly distilled vinylene carbo-

0 nate was heated for 30 minutes at 95-100 with 0.055 g. of benzoyl peroxide in a nitrogen-flushed pyrex tube, a clear non-fluid plastic product was formed. Small pieces hardened perceptibly after 15 minutes exposure to air and became hard and brittle in about two hours.

Polymer kept in a stoppered bottle did not harden. The solid, rubbery polymer was soluble in acetone and di­ me thylformamide and insoluble in cold or hot water, benzene, or chloroform (hard air-exposed polymer dissolved only in dimethylformamide). A film of polymer deposited from acetone on a salt prism showed strong carbonyl ab­ sorption at 5.55^4(1800 cm,”^).

A 0.071 g. sample of the plastic polymer dissolved after shaking for five minutes in 15 cc. of 5% potassium hydroxide. The pale yellow solution showed a good

Tyndal effect. A total of 0.337 g. of the polymer was added to the same solution in six batches - the flask

being shaken well after each addition to dissolve the solids. The last two additions brought about an opales­ cent appearance; and after being set aside overnight, the mixture set almost to a gel. When shaken, a gela­ tinous precipitate was noted which did not redissolve —62 — after adding 5 cc. of water. Filtration yielded yellow solids (0.079 g.) which became colorless when washed with dilute acid. The infrared spectrum of the solids

(in potassium bromide/aabsorption in the 3-^ (3320 cm,"*^} hydroxyl range and lack of absorption in the cyclic carbonate carbonyl range - 5.4--5. S/<((l850-1720 cm.“^).

The clear yellow-orange filtrate showed only a very weak

Tyndal effect although it still contained most of the polymer. After acidification with concentrated hydro­ chloric acid (carbon dioxide evolved), the solution be­ came lighter in color, was slightly opalescent, and showed a good Tyndal effect. Saturation with salt did not bring about precipitation.

A 1.01 g. sample of the rubbery polymer when mixed with 10 cc. of concentrated ammonia became hot and d is­ solved within 10 minutes to give a nearly colorless opalescent solution. Removal of the solvent and ammonium carbonate by heating on a steam bath gave, after drying, a hard brittle red-brown solid. The solid (in potassium bromide) showed hydroxyl group absorption at 2.9-3.1^f

(3210-3450 cm. ^) and carbonyl absorption at

(1760-1720 cm, ), A few milligrams did not appear to dissolve in 5 cc. of boiling water, but the particles lo st color and the f i l t r a t e gave a strong Tyndal effe ct. —63“

C, Addition of Bromine. - Vinylene carbonate

(8.0 g., 0,093 mole) in 50 cc. of carbon tetrachloride

was stirred and refluxed in a three-neck flask while 15 g.

(0.094 mole as Brg) of bromine was added dropwise over

a two and one-half hour period. After being refluxed

and s tirre d another hour, removal of the solvent through

a small column and distillation of the residue gave

21.4 g. (94%) of dibromoethylene carbonate ( 4, 5-dibromo-

1 ,3“dioxolan- 2-one) as a nearly white solid, b.p. 98-

102° at 12-13 mm. A sample was d is tille d twice for

analysis (b.p. 96-97° at 10-11 mm.; m.p. 29° by cooling

curve; ng^^l.5288; d^^'? 2.2824; MEg Calcd. for

G^HgO^Brg: (Eisenlohr) 3 2. 7. Found; 33.2. Strained

ring carbonyl absorption at 5.^5AA- 1830 cm. ^).

Anal. Calcd. for C 2h202Br2 : 0, 14.7; H, 0.8;

Br, 65. 0. Found: C, 15.2; H, 0,8; Br, 65.2.

A . Periodate Oxidation of Cis-bicvclo(2.2.1(hept-

5-ene-2^3-diol (A). - Sodium periodate (1.72 KC=NNq,Fb(»IOi)j CH V.ÇHOH rq A c

g HC=NNQ>H3^0%)2

0.0080 mole) in 20 cc. of water was added dropwise to

1.02 g. (O.OO8I mole) of A in 20 cc. of water in an ic e - —64— cooled flask. After the flask was shaken in the ice bath for 15 minutes, white needles precipitated and the liquid portion gave a negative test for periodate ion.

The solids were collected by filtration and washed with cold water (0,50 g., m.p. about 90° leaving a dark stain). The infrared curve showed no carbonyl absorption but did show hydroxyl absorption at 3,0-3»2M and 9.5XY

(3300 and 1055 cm,”^). A quantitative determination for iodate ion (l) showed the presence of less than 2% sodium iodate. The solids were soluble in benzene, ethanol, and hot methanol; mostly insoluble in chloro­ form and Skellysolve B; and very insoluble in ether.

Small amounts dissolved in hot chloroform or chloroform- methanol mixtures would not re c ry stallize from the cold solutions. A sample caused darkening when warmed in water and would not reprecipitate when the solution was cooled. A 0.128 g. sample set aside overnight with an excess of 2,4-dlnitrophenylhydrazine in 2% hydrochloric acid gave 0.311 g. of brown solids (theoretical yield ofhydrazone C from pure aldehyde B would be 0*500 g.).

After C was dissolved in dimethylformamide and passed through a short column of alumina, two recrystalliza­ tions from about 50^ ethanol in dimethylformamide yielded

(1 ) I. M. Kolthoff and E. B. Sandell, Textbook of Quant. Inorganic Analysis, The MacMillan Co., New York, N. Y., p . 623. -65- tiny brown-orange needles, m.p. 196-197° with darkening and loss of crystallinity at 193-196°.

Anal. Calcd. for (C); 0, 47.1; H, 3.3;

N, 23.2. Found: G, 47.3; H, 3.6; h , 23.5,

B. Attempted Dehydrochlorination of Dichloroethvlene

Garbona t e . - The procedure was the same as that used to prepare vinylene carbonate from monochloroethylene car­ bonate. After 25.0 g. (0.159 mole) of dichloroethylene carbonate and 16.4 g. (0.163 mole) of triethylam ine in

100 cc. of ether was stirred for 43 hours and refluxed for five hours, distillation of the dark filtered mix­ ture gave 1.3 g. of liquid (b.p. 95-98° at 55-56 mm.; np^ 1.455), a small second cut(b.p. 98-102° at 56-57 mm.) and 4.4 g. of mostly unreacted dichloroethylene carbon­ ate (b.p. 102-105° at 56-57 mm.; n^^ 1 .4 6 lj. The in fra ­ red curve of cut one was very similar to that for dichloroethylene carbonate; the major differences were in the degree of absorption at the various points and the appearance of a new band at 3 ,2Jj( (3120 cm.”*^). A

0.331 g. sample, after being refluxed with 25 cc. of water, neutralized 47.3 cc. of 0.1002 N sodium hydroxide.

Pure dichloroethylene carbonate, giving two moles of hydrochloric acid when hydrolyzed, would require 42.2 cc. of base; pure chlorovinylene carbonate, assumed to give one mole of hydrochloric acid and one mole of glycollic — 66- acid, would require 55.0 cc, of base.

C, Attempted Syntheses of Phenylvinylene Car­ bonate fron g-Hydroxyacetophenone

1. With Ethyl Chloroformate. - a-Kydroxyaceto­ phenone (A) would not react with ethyl chloroforma te by

o 9 CeHfCCHaOH + CICOCzHf A 1 r Base

Claisen flask to give 2.5 g. of yellow liquid (b.p. about 14.5- 160® at 3-4- mm.). Redistillation yielded a little unreacted A (b.p. 133-14.5° at 3- 4. mm.) and 1.9 g,

{25%) of impure i B (b.p. 14.5-153° at 2-3 mm.). Impure B , 27 was redistilled twice again (ng® 1 . 515; d, 1.16 - 0.1 cc, 4 4 picnometer; MR^ calcd. for ^]_x^l2^4* 52.6. Found: 54.2, Strong carbonyl absorption at 5.68>

5.85y%(l710 cm,"^).

Anal. Calcd. for (B); G, 63.4; H, 5.8. -67-

Calcd. for CgHgOg (A); C, 70.6; H, 5,9. Found; C, 64.7;

H, 5.8.

To 1.5 g. of impure B in 25 cc. of dry ether was added dropwise with s tirrin g 22 cc. {7% excess) of

0.035 M sodium triphenylmethyl (1) in ether. Since de­ colorize tion of the red base solution was slow, the addi­ tion was carried out over a four period followed by two hours of stirring. After filtration, concentration of the filtrate yielded 4.5 g. of solids which were ex­ tracted with 25 cc. of pentane leaving a small amount of orange oil. Rapid d is tilla tio n of the o il, above

180° at 3-4 mm., yielded 0.40 g. of yellow solid. The infrared spectrum of the distilled material was practi­ cally identical with that for triphenylmethane (m.p.

92-94*^) obtained from the pentane extract.

2. With Phosgene. - After 11.1 g- (0,112 mole) of phosgene was collected in an ice-cooled three-neck flask containing 50 cc. of dry toluene, 13.1 g. (0.096 mole) of A in 100 cc. of chloroform was added rapidly with stirring. After the mixture was kept at 0° for

16 hours and stirred at room temperature for two hours, the solvent and excess phosgene were distilled under

(l) R. B. Renfrew, Jr. and 0. R. Hauser, Organic Syntheses, John Wiley and Sons, In c., New York, Coll. Vol. II, p. 607. -68- vacuum through a column (toluene trap ). The infrared

curve of the remaining crystalline residue differed

only slightly from that of k.

Unreacted A from the first experiment was refluxed for eight hours with a mixture of 10.5 g. (O.IO 6 mole)

of phosgene and 20.0 g . (0,198 mole) of triethylam ine in 100 cc. of chloroform. After being successively

shaken with water dilute acid, dilute sodium bicarbonate, water, and saturated salt so lu tio n and filte re d through anhydrous sodium s u lfa te , removal of chloroform and d is­ tillation gave 9.5 g. of colorless liquid (b.p. 61-66° at 6-7 mm.) and 1.9 g. of A. The sweet smelling liquid was diethylcarbamyl chloride (66% based on phosgene).

A sample was redistilled twicej (b.p. 75-77° at 12-13 mm; 20 20 njj 1.4500; dj^ 1.067; MRj, Calcd. for C^H^qONCI: 34.1.

Found: 34.2). An authentic sample of diethylcarbamyl

chloride (Monsanto) was d is tille d (b.p. 77-78° at 14-15 mm.; 1.4508). The two materials had identical in­ frared cruves.

When 26.0 g, (0.263 mole) of phosgene was refluxed for 15 hours with 34.7 g, (0.343 mole) of triethylamine

in 100 cc. of chloroform, the yield of diethylcarbamyl

chloride was 28.5 g. (80%). An investigation of the literature revealed that two analogous reactions had —69— been reported. (1,2)

D, Friede1-Crafts Reaction with Monochloroethylene

Carbonate and Toluene. - After 10.0 g. (0.0816 mole) of monochloroethylene carbonate was stirred in a three-neck flask with 75 g. (0.82 mole) of dry toluene and 18.6 g.

(0.14 mole) of aluminum chloride was added over a 30 minute period, the mixture was heated and hydrogen chlor­ ide did not appear until a temperature of 85° was reached.

After being heated at 85-100° for one and three-quarter hours, the mixture was poured into an ice-dilute acid mixture. After extraction with benzene, the organic portion was washed in the usual manner. The concentrate was distilled and two liquid cuts were collected:

(1) 3.74 g.J b.p. 107- 140° at 1-2 mm. and (2) 3.89 g.j

140-165° at 1-2 mm. A little solid material present in each cut was removed by dissolving the cuts in hot ethanol, cooling and collecting the small plates on a filter. Cut 1 yielded 0.06 g. and cut 2 yielded 0.24 g. of solids. Another 0.42 g. of yellow solids was obtained by passing the distillation pot residue (in benzene) through an alumina column and cooling the concentrated

(1 ) V. A. Rudenko, A. Yakubovitoh, and T. Nikiforuva, J. Gen. Chem. (USSR) 12, 2256 (1947). C. A., 42, 4918. (2) R. P. Lastovski, J. Applied Chem. (USSR) 19. 440 (1946). C. A., 41, 1214. -70- elutriate. The liquid products were redistilled (97-

150° at 1-2 mm.) with the refractive index for four cuts changing from 1,545 to 1.602. The infrared curves showed no carbonyl, hydroxyl, or ether type absorptions.

The fractions contained no chlorinated product and were apparently hydrocarbon mixtures. The solids from the reaction were recrystallized from ethanol and from Skelly- solve B and then vacuum sublimed (m.p. 225.4-226.2°.

Anal. Found: C, 93.3; H, 6.8), No readily deduced re­ action product (p,p^-dimethylstilbene, 9,10-dihydroanthra- cene, etc.) fit these data; and since the compound re­ presented a minor product (0.66 g. out of 7.6 g.), it was not investigated further.

The Friedel-Craft reaction when carried out at 80° for two hours using 10.0 g. (0.082 mole) of monochloro- ethylene carbonate, 100 cc. of toluene, and 13.0 g.

(0.098 mole) of aluminum chloride, produced sim ilar results although there was less solid formed and the liquid fraction distilled over a lower boiling range.

E. Dichlorocthvlene Carbonate and Ethylene Glvcol. -

A fter 2.64 g. ( 0.0168 mole) of dichloroethylene carbon­ ate was refluxed for four hours with 5.7 g. (0.092 mole) of ethylene glycol in 6 cc. of benzene (strong hydrogen chloride evolution), removal and evaporation of the ben­ zene layer yielded 1.75 g. of white solid. Recrystal­ liz a tio n from about 25 cc. of ether gave, first. -71- pyrimidal crystals, m.p. 134.6-135.6°. A second crop consisted of more of the same material plus a small portion of long crystals which were separated by hand, m. p. 111-113°; mixed with first crop, m.p, 90-110°,

The infrared spectra of the two compounds showed strong absorptions in^elher range (B .6 -9 ,5 M ) but no carbonyl absorption. Without further investigation, it was con­ cluded that the materials (75^ yield) were the cis and trans forms of glyoxal-bis-ethylene acetal, m.p. 109-112° and 133-136°. (l) The products were the same when the reaction was carried out with about equimolar amounts of dichloroethylene carbonate and ethylene glycol in a dilute refluxing benzene mixture,

F, Chlorination of Fronvlene Carbonate. - Chlorine was passed into 102 g , (1,0 mole) of propylene carbonate in the previously described chlorination apparatus

(U,V, light) until the increase in weight was 35 g.

Initially, the carbonate was heated to 60°; but the re­ action was exothermic and the carbonate temperature fluctu­ ated between five and ten degrees above the bath tempera­ ture of 60-70°. The increase in weight was 21 g. within five hours when the passage of chlorine was steady,

(l) J. Bceseken, F, Tellegen, and P. C, Henriquez, Rec, trav. chim., 909 (1931). -72-

Fractlonatlon of the reaction mixture through a 25 cm,

column indicated that several products were formed.

Twelve fractions were collected, each of about five to ten grams with the boiling points changing steadily from 2 c 71° at 24 mm. to 123° at 12 ram.j n^ from 1^4300 to

1,4532 with an interm ediate maximum and minimum of

1.4402 and 1 .4364. -73-

SÜMMARY

1. Ethylene carbonate was chlorinated to yield 60

to 69/^ monochloroethylene carbonate (4.-chloro-l, 3-

dloxolan-2-one) and 5 to 15^ dichloroethylene carbonate

(4,5-dichloro-l,3-dioxolan-2-one),

2. Vinylene carbonate (l,3-dioxol-2-one) was

prepared in 12% yield by the dehydrochlorination of mono-

chloroethylene carbonate with triethylamine and in 29

yield by the elimination of chlorine from dichloroethylene

carbonate with zinc dust.

3. The structure of vinylene carbonate was proved by hydrogenation to ethylene carbonate and by hydrolysis

to give glycol aldehyde (phenyl osazone).

4. Solid Diels-Alder adducts were prepared from

vinylene carbonate and the following dienes (adduct yeilds in parenthesis); butadiene (26^), 2,3-dimethyl-

butadiene (61%), cyclopentadiene (77%), hexachlorocyclo-

pentadiene (80%), anthracene (88%), and furan (34%).

No adduct was obtained with 3,4,3^\4^-tetrahydro-7,7^-

dimethyl-l,l^-binaphthyl.

5. The Diels-Alder adducts (except for hexachloro-

cyclopentadiene) were converted to the corresponding

glycols from which the structures were established by

conversion to known compounds. —74~

6, Vinylene carbonate was polymerized to yield solid polymers with the repeating unit 0 , C.

lA ln Hydrolysis of the polymer converted part or a ll of tne units to rOH OH % 7. Dibromoe thylene carbonate (4., 5-dibromo-l, 3~ dioxolan-2-one) was prepared by adding bromine to vinylene carbonate. TABLE V

DIELS-ALDER REACTIONS WITH VINYLENE CARBONATE

Run Ratio No, Diene V.C, to Temp Time Solvent Product Diene OQ Hrs,

A. 1 2,3- 0,67 100 16 Benzene 0 2 Dimethyl- 0,55 1 0 0 -1 2 0 25 — 0 3 butadiene 0,62 1 4 5 -1 5 0 6 Benzene 0 4 0.66 140-150 13 — 11a 5 0,59 1 7 0 -1 7 3 5 Toluene ,c = o 27a 6 0,49 1 7 0 -1 8 0 10 Toluene - 0 37a 7 0,26 1 7 0 -1 8 0 16 Benzene 54a 8 3.8 1 7 5 -1 8 5 15 Benzene 6 ia 9 3.8 200-205 6 Benzene 48 10 1 6 0 -1 6 5 13 Benzene 60S 9.7 59a 11 7.3 140-147 16 Benaene 12 9.2 1 7 5 -1 9 0 7 Benzene 48a

P. Butadiene 2.6 1 7 3 -1 7 5 19 Benzene 26®

C. 1 Cyclo- 2,9 1 7 0 -1 7 7 16 Benzene 76A 2 pentadiene 3.A 1 7 0 -1 7 7 14 Benzene ,c=o 77A 3 (dimer) 1,9 1 7 0 -1 7 5 15 Benzene 76A IB o ofA) o D. Hexachloro- 5.0 1 7 7 -1 8 3 26 Benzene (6> 80 cyclopenta­ diene -CCI

E. Anthracene 8,3 1 6 0 -1 7 0 12 Benzene 88

CH-O' TABLE V, Cont.

Ratio Run r.c. t 0 Temp, Time Solvent Product % No. Diene Diene °G Hrs. Yield'

1 1?uran 3.0 137-143 21 Benzene 23c 7.5D 2 3.7 135-145 3 Benzene 35C&D* 160-170 6 3 3 .7 135-150 16 Benzene 32C&D* 4 4.2 112-118 17 Benzene 18G&Da 5 5.0 123-127 19 Benzene 34c® 6 9.8 102-108 43 Benzene 23c® 7 3.1 Room 146 - 0 days (D) G. 1 10,0 165-170 14 Benzene 0 10.7 205-210 20 Toluene 0 1 3 .6 Reflux 6 days Xylene 0 13.0 2 18-222 63 Xylene 0 9.6 178-182 33 Benzene 0 (methyl borate added)

1 , Based on the reactant present in the lowest concentration. a. Distilled but not recrystallized; otherwise figures represent re crystallized products. 100

8 0

60

40 Ethylene carbonate 1.4% in CHCI 3 20 0.2 mm. cell ? FIGURE I CD w 0-100 P, 0 11% in CHCUi 0 2 mm. cell 1 «0 CO o I 2 •i « c (/) T3 CD z O < c+ H I IT H* X t- O 40 Monochloroethylene M I- z carbonate oUJ 20 Liquid on sandwich at cell CD K FIGURE 2 O 0-100 Ct v>.2mm. cell; 1.5% in CHCI p 80

60

40 Dichloroethylene carbonate 20 Liquid on sandwich ceil FiGURE 3

WAVELENGTH IN MICRONS

FIGURES I, 2, 3 100

80

60

40 Dibromo ethylene corbonote 20 1.8% In CHCI; 02 mm. cell FIGURE 4 1.5% in CHCI ; 0.2mm. cel------80 V A . rvK r K -

60 I <3 -C 4 0 I I- z Vinylene Corbonote oUJ 20 (£ w Sondwich Cell 0. FIGURE 5 0-1 00

80

60 ,CH;

40 1% in KBr wofer CHg 20 2.8% in CHCI 3 0.2 mm. cell FIGURE 6

WAVELENGTH IN MICRONS FIGURES 4, 5, 6 100

80

60 HC^^^'"CH-0^ 11 1 C=0 40 CH-0 "S h 20 1.3% in CCI*0.2mm. cell FIGURE 7 0-100 UJ o z < 80 I- I- Z i v> 60 < 1 z 00 ) KBr wofer I- 4 0

I- CH z 111 20 o 0.2 mm. cell cc UJ figure 8 0-100

8 0

60

40 O X I x > - ° 1.1% in e c u 20 0.2 mm. cell FIGURE 9

WAVELENGTH IN MICRONS

FIGURES 7. 8 ,9 an

100

8 0

60

4 0 :c=o

20 1% KBr Wafer FIGURE 10 0-100 UJO z g 80 I-

60 I <3 CO 40 I I- Nujol Mull o 20 (T FIGURE II UJ 0-100

118% in CHCJs; 80 0.2rr«(n. cell

60

HO 40 CH 20 m . p . 149° > KBr Wafer FIGURE 12

WAVELENGTH IN MICRONS

FIGURES 10, II, 12 100 1.6% In CHOU 0.2ml

80

60 CH HC C H -0 4 0 :c=o HC -CH-""'' 20 m.D. 136° 1% KBr Wafer FIGURE 13 0-100 z 80 I- S I cn 60 CD z 0 a:< 1 t- 40 I- C=0 z w 20 (To 1% KBr Wafer liJ FIGURE 14 a. 0-100

80

60

40

4-t-bufoxy- l,3-dioxol-2-ane 20 Nujal Mull FIGURE 15

WAVELENGTH IN MICRONS

FIG UR ES 13, 14, 15 100

60

60

40

20 Nujol Mull FIGURE 16 w 0-100 o 80 t S I OT 60 CD z M ce< 1 40 »- z ^CH ^OH ü 2 0 (T Nujol Mult ÜJ FIGURE 17 “ ■ 0-100

80

60

40 -CH—CH— 20 Film on Soif Prism FiGURE 18

WAVELENGTH IN MICRONS

FIGURES 16, 17, 18 100

8 0

60

4 0 Vinylene Corbonote Polymer Hydrolyzed in KOH Solution 20 1% in KBr Wofer.

FIGURE 19 < 0-100 CD

8 0 UJ

60

4 0 Vinylene Corbonote Polymer Hydrolyzed m Cone. Ammonio 20 1% KBr Wofer FIGURE 20

WAVELENGTH IN MICRONS

FIGURES 19, 20 28

d 0

w0)' 3 O u » 0) Q. Completely CD I 22 ' solid

Both Temperature 7 -9 20

0 510 15 20 25 30 Time, Minutes

FREEZING POINT CURVE - FRACTIONATED VINYLENE CARBONATE ( P 3 i )

APPENDIX n «*84—

AUTOBIOGRAPHY

I, Roger Williams Adder, was born in New Rochelle,

New York, un April 30, 1926. My elementary and second­

ary school education was obtained in the public schools

of Poughkeepsie, New York. I received the degree

Bachelor of Science in 194-9 and the degree Master of

Science in 1951 from the University of Maine. While

at Maine, I served two years as a Teaching Assistant

in the Department of Chemistry. During my residence

at The Ohio State University, I received an appointment

as Research Fellow in the Department of Chemistry for

the years 1952-54- 1 also acted as A ssistant during

the year 1 9 5 1 -5 2 and as Research Assistant during the

summer of 1954 while completing the requirements for

the degree Doctor of Philosophy,