A Study of the Charge Distribution in Unconjugated Thiocarbonyl Compounds: a Comparison with Carbonyl and Imine Chromophores

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1974

John Yuchu Lee

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Recommended Citation Lee, John Yuchu, "A Study of the Charge Distribution in Unconjugated Thiocarbonyl Compounds: a Comparison with Carbonyl and Imine Chromophores" (1974). Electronic Theses and Dissertations. 4734. https://openprairie.sdstate.edu/etd/4734

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THE CARBONYL AND IMINE CHRO!-DPHORES

. BY

JOHN LEE YUCHU

�.UTH _DAKOTA STATE UNIVERSITY LIBRARY

thesis A su:C:-:iitted fulfill::1ent of the the in partial requirer,ents for degree in Master of Cheriistry, Science, ��jor South Dakota State Unive1·sity

1974 '1, I

A STUDY OF THE CHARGE DISTRIBUTION IN UNCONJUGATED

THIOCARBONYL COMPOUNDS: A COMPARISON WITH

THE CARBONYL AND IMINE CHROr-OPHORES

Abstract JOHN YUCHU LEE

Under the supervision of Dr . James Worman

Via a literature search it has been shown, by means of the ira spectra of thioamides, the dipole moments of thiocarbonyl compounds , the basicity of thioamides and thioureas, the acidity of carboxylic

acids carrying a substituent with the thiocarbonyl function, LCAO-b

method, and proton· chemical shifts, that the thiocarbonyl group me has tendency to give a greater mesomeric interaction than the (�) carbonyla group (£) with electron donating heteroatoms.

II r;; -q�c - x -dc - x

Io e

I = molecules, calculating the forces constants from the ir absorption frequencies,

measuring the bond distances by x-ray, and observing the proton

chemical shifts in the nmrd spectra. The use of the electronic absorption spectra, molecular orbital theory, and mass spectrometry are also included.

All data support the hypothesis that the thiocarbonyl chromophore has more ionic contribution to the resonance hybrid than is present in

or This is not predictable on the basis of the electronega- (£) (�). tivity of the heteroatoms .

- 0- N/ s 0 0 0 II II II 0 c o + c o + + c /\ /\ I\

(£) (£) (�) a ir = Infrared . CAO = Linear Combination of Atomic Orbitals chr. M) = Molecular Orbital d nmr = nuclear magnetic resonance A STUDY OF THE CHARGE DISTRIBUTION IN UNCONJUGATED

THIOCARBONYL COMPOUNDS: A COMPARISON WITH

THE CARBONYL AND IMINE CHARO�DPHORES

Th is thesis is approved as a creditable and.independent

investigation by candida te for the degree, Ma ster of Science, and

is acceptable as meeta ing the thesis requirements for this degree.

Acceptance of this t.hesis does not imply that the conclusions reached by the candidate are neces sarily the conclusions of the major depart ment.

sis Adviser Da e M' / f

Head, Chemistry Department Da te Emma Lee and G. To Ornodt ACKNOWLEDGMENTS

wish to express my deepest tha nks to Dr. James J. Worman, under I whose direction this thesis was prepared, for his continuous encour

agement and helpful suggestions during the course of this investi

gation.

also would like to thank all the staff in the Chemistry I Depa rtment.

At last, my thanks goes to Mrs. Betty Prunty for typing this

thesis.

JYL TABLE OF CONTENTS

Page

HISTORICAL SURVEY OF CHARGE DISTRIBUTION IN CON JUGATED CARBONYL TH IOCARBONYL COMPOUNDS • 1 AND PURPOSE ...... 11

RESULTS . . . . 12 METHODS AND Dipole Moment 12

Infrared Spectroscopy • • 13

X-Ra ·� . • • • • • • • • • . . . 16 Nucleary Magnetic Resonance Spectroscopy 18 Electronic Spectroscopy • • • • • • • • 24 Mass Spectra 24 . • • • • •

Melting Point ••• 26 •••••••••

DISCUSSION ...... 27

38 CONCLlJS:!:ONS . . . . .

EXPERIMENTAL . 39 . .

of Instrumentation Used 39 Description • • . •

Preparation of Diethylketals • 39 . • • • ne 40 2,2-Diethoxy-1�3-diphenylpropa . • • • • • • • • 40 Preparation of Thiones . • . . • • • • • • • 40 l,3-Diphenyl-2-propanthione XXXII . • 41 ( ) Preparation of Tetramethyl-1,3-cyclobutanedithione XXIX •• 41 Preparation of N,N'-Dicycloheptyl-2,2,4,4- ( )

tetramethyl-l,3-cvclobutanediimine • • • • • • • • • 42 Preparation of the N-n-butyl imine of 1, 3-

diphenvl-2-propanone XXXIII . • • • • • 43 ( ) REFERENCES 44

APPE IX 47 ND LIST OF TABLES

Table Page

1. DIPOLE JvOMENT DEBYE OF SOME CARBONYL AND THIOCARBONYL COMPOUNDS( ) R1 C = X X = 0, S . . . 1 R2 ) ( ) . . . 2. CALCULATED VALUES FOR THE SYSTEMS VII-XVII , AND�µ VALUES FOR µ,TIVII-� AND XII-XVII IN DEBYE( UNITS.) THE DIRECTION IS( C ) X ( ) • . 3 • • • • • . • •

3. ACID DISSOCIATION__... CONSTANTS . . 7

4. PROTON CHEMICAL SHIFTS OF THE METHYL GROUPS OF ACET. AMIDE AND THIOACETAMIDE • • • 9 • • • • • • • • • • • •

5. DIPOLE M)MENTS OF SOME SIMPLE MOLECULES 12

6. INFRARED SPECTRA OF 2,2,4,4-TETRAMETHYL-l,3- CYCLOBUTANE-DIONE, 2,2,4,4-TETRAMETHYL-l,3- CYCLOBUTANE-DITHIONE, THE IMINE OF 2;2,4,4- TETRAMETHYL-l,3-CYCLOBUTANEDIONE, 1,3-DIPHENYL- 2-PROPANONE,l,3-DIPHENYL-2-PROPANETHIONE, AND THE IMINE OF l,3-DIPHENYL-2-PROPANONE •• 13 • •

7. FORCE CONSTANTS CALCULATED FROM TABLE 6 14

8. DOUBLE-BOND DISTANCES FROM THE CRYSTAL SffiUCTURES OF 2,2,4,4-TETRAMETHYL-l,3-CYCLOBUTANEDIONE,26 2,2,4,4-TETRAMETHYL-l-3-CYCLOBUTANEDITHIONE,27 AND 8 THE IMINE OF 2,2,4,4-TETRAMETHYL-l,3-CYCLOBUTANEDIONE2 16

9. NMR SPECTRA OF 2,2,4,4-TETRAMETHYL-l,3-CYCLOBUTANEDIONE, 2,2,4,4-TETRAMETHYL-l,3-CYCLOBUTANEDITHIONE, THE IMINE OF 2,2,4,4_TETRAMETHYL-l,3-CYCLOBUTANEDIONE, 1,3- DIPHENYL-2-PROPANONE, 1,3-DIPHENYL-2-PROPANETHIONE, NYL-2-PROPANONE OF 1,3-DIPHE • AND THE IMINE • • 18 • •

10. PROTON CHEMICAL SHIFT OF METHYLENE HALIDES X F, C 1, Br, I 1 -CH -X, • • 9 = • • • • ( 2 ) 11. ELECTRONEGATIVITY OF HALOGEN ELEMENTS 20 · Table Page 12. PROTON CHEMICAL SHIFT OF METHYL HAL IDES • 21 13. ELECTRONIC SPECTRA OF l, 3-DIPHENYL-3�PRO PANETHIONE33 AND 2, 2, 4,4-TETRAMETHYL-l,3- CYCLOBUTANEDITHIONE . . . • • . . 24 • • • • • • • • • . 14 . MASS SPECTRA44 OF 2, 2, 4, 4-TETRAMETHYL-l,3- CYCLOBUTANEDIONE, 2, 2, 4, 4-TETRAMETHYL-l, 3- CYCLOBUTANEDITHIONE, THE IMINE OF 2,2, 4, 4- TETRAMETHYL-l,3 -CYCLOBUTANEDIONE • • • • • 25

15. MASS SPECTRA45 OF 1,3-DIPHENYL-2-PROPANONE, 1, 3-DIPHENYL-2-PROPANETHIONE, AND THE IMINE OF. 1, 3-DIPHENYL-2-PROPANONE . . •••• •••• . 25 . . . . 16. MELTING POINT OF 2,2, 4,4-TETRAMETHYL-l, 3- CYCLOBUTANEDIONE, 2, 2, 4, 4-TETRAMETHYL-l,3- CYCLOBUTANEDITHIONE, THE IMINE OF 2,2, 4,4- TETRAMETHYL-l,3 -CYCLOBUTANEDIONE 26 ••••• LIST OF FIGURES

Figure Page 1. Double-bond distances vs. different functional

groups • • • • • • • • • • • • • • • • • ...... 17 2. Proton chemical shifts of methylene vs. the electronegativity of halogen elements ...... 20 . 3. Proton chemical shifts of methyl halides vs. the electronegativity of halogen elements ••••. . . . 21 4. Comparison of chemical shifts of methyl hydrogens of 2,2,4, 4-tetramethyl..:l ,3-cyclobutanedione, 2,2,4,4- tetramethyl-l, 3-cyclobutanedithione and trans-N,N' dicycloheptyl-2,2,4, 4-tetramethyl-l, 3-cyclobutane-

di imine • • • • • • • • • • • • • • • • • • • • • • 22 5. Comparison of chemical shifts of methylene hydrogens of 1,3-diphenyl-2-propanone, l,3-diphenyl-2-pro panethione, and N-n-butyl-1, 3-diphenyl-2- propaneimine . . . . . 23 . 6 ...... Energy diagram for nmr . . . . 28 .

7. Diamagnetic shielding of nucleus by circulating ...... electrons ...... 29 . Perturbation of electron cloud around a proton by s. inductive withdrawal by an electronegative substituent (X) . . 30 • • • • • • • • • • • • • . • • • 9. Representative atomic orbitals 32 ••••••••• 10. Valence electron orbitals of the sulfur atom 33 •• 33 ll. A 2p-2p TT�bond • • • •

12. A sp-3p rr-bond . . . 34 • • • • • • 34 13. A sp-3d bond •• . 14 . ·A sp2-3p cr-bond, partial 2-3p rr-bond, and partial 2p-3d rr-bond • • • • • • • • • • • • • • • • • • • • • • • 35 15 . ·Ionic mechanism of dimeriza ti on of two thiocarbonyl groups 36 • • • • • • • • • • • • • • HISTORICAL SURVEY OF CHARGE DISTRIBUTION IN CONJUGATED

CARBONYL AND THIOCARBONYL COMPOUNDS

2 Luttringhaus et fil· observed1' that the dipole moments (Table 1)

of thiocarbonyl compounds exceed those of the corresponding carbonyl

compounds if, and only if, subs tituents c9pable of strong mesomeric

electron release were present in the molecule (1,-VI).

< I foot r.. @ C = s = c - y ( ) s9 - c = y > Se - y ffi

I (11.)I (III)I (1.)

< I " oe - = c C.·- y ( ) 08-c=yffi c..; y - O= > m

(IV) (VI) (y)

TABLE 1. DIPOLE MO��NT (DEBYE) OF SOME CARBONYL THIOCARBONYL AND COMPOUNDS R 1

= = 0, S) x R (X 2/"'c

R µc = o µc = s (µc=o-µc=s) 1 R2 .6µ,

2 Cl Cl 1.18 0. 8 +0.903 CH o CH30 . 3 0.87 0.90 0 0 33 - CH S CH3S 1. 3 0.74 -0.59 6 CH3 3.74 4.7 1 02 (CH3)2N . 3 4.44 - p-CH oc H p-CH30C6H4 3 6 4 . 90 -0.54 3.54 3.94 -0.40 p-CH3SC6H4 p-CH3SC6H4 2

Janssen3 reproduced this mesomeric tendency by a simple LCAO-MO method. A model based on two considerations, in order to select 7 parameters , 4,5,6 was chosen: ,8

1. The c-s and c=s bonds are polar.

2. Sulfur does not form double bonds as do first-row elements.

With this model calculations were performed according to Huckel's LCAO procedure , modified by the w-technique , 9,10 until self-consistency was . obtained. The result showed that both an element of electron at traction and a low resonance integral are required for the thiocarbonyl group in the present approximation in order to bring out the general polarization characteristics observed. Furthermore , Janssen calculated the difference between the dipole moments of a series of conjugated carbonyl compounds and those of the thiocarbonyl compounds. It was shown to be in qualitative agreement with literature values (Table 2). 3

TABLE 2. CALCULATED µTI VA LUES FOR SYSTEMS AND�µ VALUES FOR AND THE DEBY(VII-XVII),E UNITS . DIRECTION IS(VII-X) C (XII-XVII) IN THE � X.

�µ, �µ, 0 µ,TI S TI ca Reference X= X= le

(VII) 1.03 0 1.03 -0 .85 1.03 0 1.03 -0 . 85

(VIII) 1.56 2.04 -0 .48 -0.32 11, 12 1.40 1.76 -0.36 -0. 25

(IX) 3.36 5.39 -2 .03 -1.87 3.05 4.69 -1 .64 -1 .52

2.52 4.04 -1 .52 -1 .36 (f) 2.29 3.49 -1 .20 -1. 10

3.27 5.18 -1.19 13, 14 (XI) 2.94 4 .43 -1 .49

(XII) 4.35 7.04 -2 .69 -2 .53 15, 16 3.96 6.19 -2.23 -2.21

(XIII) 2.08 2.33 -0.25 -0.09 1.86 1.97 -0 .11 0

(XIV) 2.51 2.88 -0 .37 -0.21 2.38 2.51 -0 .13 -0.03·

(XV) 4.31 5.19 -0. 88 -0.72 3.91 4. 42 -0 .51 -0.41

(XVI) 3.46 4.17 -0 .71 -0.55 3.30 3.63 -0 .33 -0�23

(XVII) 5.81 7 -1 .30 -1.14 .ll 5.13 5.99 -0 . 86 -0.76 4.29 + . 52 +0 .67 5 . 81 1 4

Cl RO

Cl RO (VIII) (IX)

RS R2N R2N

= = = >c x >c x >c x RS R2N R2N (XI) (XII) (v' �I

p-ROC H C6H5 p-ClC6H4 6 4

= = = x x x > c > c p-ROC >H c C6H5 p-ClC6H4 6 4 (XIII) (XIV) (XV)

Systems found in Table 2 5

The calculated µ and 6µ values are found in Table 2. There are some discrepancies between experimental and calculated 6µ values . The most serious deviation is shown by the phosgenethiophosgene_ system VIII , where the experimental and calculated values have different ( ) signs. It is obvious that the simple model will always give a negative

6µ value, as long as only the conjugation effect is considered . How ever, the presence of the two strongly electronegative chlorine atoms will disturb the systems of both and electrons apart from the direct action of the core field . TTA similara effect is expected for other systems in which the substituents are strongly electronegative .

The agreement between experimental and calculated�µ values is con siderably better for the benzophenone-thiobenzophenone systems than for the simpler ones, probably because the inductive effect of the atom

is less important . Thus, the discrepancies are consistently explained y by the operation of inductive effects, either on the or on the or both. In general , one can, therefore, conclude thata, a more rapiTTd, increase in polarity of the thiocarbonyl compounds than of the car bonyl compounds is occurring with increasing electron release from the substituents . 6

Jensen! 7 has pointed out that the. ir spectra of thioamides indicate that the structure (XVIII) has greater weight than com pound (XIX), whereas the reverse is true for amides (XX), (XXI) .

R / S = C - N...... _ R' I (XIX) (XVIII)

R = C N/ 9 � / R - C = N 0 0 - ...... 'R' I R' (XXI)

Jensen18 studied the acid strengths of compounds containing the thiocarbonyl group . Compounds were of general type X = C - BCH2COOH, AI with A = methyl, alkoxy, alkyl thio or dimethylamino, X = oxygen or sulphur, B = oxygen, sulphur or nitrogen.

The acid dissociation constants of a number of supstituted acetic acids were determined (Table 3). In the molecules studied the thio- carbohyl group is more electron-attracting than the carbonyl group . 7

TABLE 3. ACID DISSOCIATION CONSTANTS .

Essentia l Structural Compound Part pKc

S-Carboxymethyl dithioa cetate s 2.99 c?' ' s- o S-Carboxymethyl thioa cetate � 3.23 c ' s-

S-Carboxymethyl-N,N-dirnethyl dithiocarbarnate N - C ,s 3.38 's- ·

S-Carboxymethyl-N,N-dirnethyl N - ?'o thj_oc8rbarnate G"' 3.55 '-��

0-Carboxymethyl-N,N-dirnethyl C s 2.87 thionocarbarnate N - � 'o-

0-Ca rboxymethyl-N,N-dimethyl 0 carbamate N - C 3.01 � '-o-· 8

On the basis of the electronegativities of oxygen and sulphur ,

it would be expected that the oxygen atom would be more electron-

attracting so that the carbonyl acids would be stronger , but the

result in Table 3 shows that the naive electronegativity considerations

are not permitted at all. This means that the C = S group is strongly polar and it has the smaller tendency to form double bonds (XXI, XXII).

A -(sC - B - CH C - H II .n.- 2II - 0 (XXXI)

0 A-Is -cH -o.- i 2 L (XXII) J G

The basicity of the thiocarbonyl group in thioamides49 protonated in concentrated acids has been studied. Some complications arise when the (thio) carbonyl group is attached to an amine functional group , because the amino group might also act as the basic site. However, in a number of publications19,20,2l,22 compelling evidence has been pre- sented that in these corr1pounds the proton becomes praferentially attached to the double-bonded oxygen or sulphur atom (XXIII-XXVI) . 9

(XXIII)

SH s H� + - C - N( - C - N( II > II (XXV) (XXVI)

It is obvious that the formation of these· sulphonium ions is chiefly due to change in n-electronic structure.

The author observed the.alkyl proton chemical shifts of acetamide and thioacetamide (Table The larger value of the methyl group 4). 6 of thioacetamide may be due to the deshielding effect of the positive charge on the carbon atom in the thiocarbonyl group (XXVII). More details are given in the Discussion Chapter.

TABLE 4. PROTON CHEMICAL SHIFTS OF THE METHYL GROUPS OF ACETAMIDE AND THIOACETAMIDE .*

Formula Compound Proton Chemical Shift (DMSO)

Acetamide 1.68 0

Thioacetamide 2 ..25 0

See spectra pages 51, 52.

* 10

II - CH3�C NH o& (XXVII)

All of the foregoing information indicates that the thiocarbonyl

chromophore is more polar than the carbonyl chromophore when it is atta ched to atoms capable of conjugation with the chr ornophoric pi-bond. PURPOSE

It was the purpose of this work to determine the charge distri bution in the unconjugated thiocarbonyl chromophore using as many physical methods as possible. A comparison with the carbonyl and irnine chromophores is intended in order to understand more fully the effect of carbon pi-bonded to oxygen, nitrogen, and sulfur in structur ally similar environments. METHODS AND RESULTS

Dipole Moment*

TABLE 5. DIPOLE fvOMENTS OF SOME SIMPLE l-ULECULES.

Formula Compound µ(D) 23 co Carbon monoxide 0.130 (g) 23 cs Carbon monosulfide 1.97 (g) 1.84 (g}24 H20 Water 24 0.950 (g) H2S Hydrogen Sulfide 25 2.29 (g) H2co Formaldehyde 1.65 (g) 29 H2cs Thioformaldehyde

* - These data have been obtained from the literature.

g - gas 13

Infrared Spectroscopy

TABLE 6. INFRARED SPECTRA OF 2,2,4,4-TETRAMETHYL:-l,3-CYCLOBUTANE DIONE,2,2,4,4-TETRAMETHYL-l, 3-CYCLOBUTANE-DITHIONE , THE IMINE OF 2,2,4,4-TETRAMETHYL-l, 3-CYCLOBUTANEDIONE , 1,3-DIPHENYL-2- PROPANONE ,l,3-DIPHENYL-2-PROPANETHIONE , AND THE IMINE OF l,3-DIPHENYL-2-PROPANONE.

-1 Compound C = X Bond Frequency (cm )

(XXVIII) 1750 a

1265 b,41,42

1670 c,43

1720 d

. asee spectra page 55. bsee experimental pages 41, 42. csee experimental page 43. dsee spectra page 47, experimental page 39.

...... _.,_iO._UTH .. - .OAKOJA SIA.TE UNlVERSlTY LU}RA� 294447 14

TABLE 6. Continued.

Compound C = X Bond Frequency (cm-1)

(XXXII) 1100 e ,4o

(XXXIII)

- 1 f 1 Calculation: --- 2rrC MxMy )2 \) - - Mx +My

_;f___ _ 2c2v2 = _ 4rr MxMy Mx +My

f = MxMy (4rT 2c2v2) + My Mx e see spectra page 50, experimental pages 39-41. f see spectra page 48, experimental page 43. 15

TABlE 7. FORCE CONSTANTS CALCULATED FROM TABLE 6.

Compound Force Constant of C = X Bond dynes/cm

1 .45 io29 x

5.04 io29 s=z>=s x

6.20 io29 x

1.25 io29 x

3.84 io29 x

6.20 io29 x 16

X-Ray

TABLE 8. DOUBLE-BOND DISTANCES FROM THE CRY L STRUCTURES OF 2,2 ,4, 4-TETRAMETHYL-1,3-CYCLOBUTANEDIONE,�kf 2,2,4,4-TETRAMETHYL-l- 27 3-CYCLOBUTANEDITHIONE, AND THE HllINE OF 2,2,4 ,4- TETRAMETHYL-l , 3-CYCLOBUTANEDIONE . 28

0 Compound Doubl e-Bond Distance A ( )

1.20

1. 61

1.30

r\J· 17

2.0

1.8 1. 61 1.6 CL> (.) It:- 1.4 ...,.....1.34 *"""'1. 30 c: 1. 20 co 1.2 +> (/) •r-i � Q LO "O c: 0 .8 m

0 C=C C=N C=O C=S

Figure 1. Double-bond distances vs. different functional groups. 18

Nuclear Magnetic Resonance Spectroscopy

TABLE 9. NMR SPECTRA OF 2,2,4,4-TETRAJv'lETHYL-l,3-CYCLOBUTANEDIONE , 2,2,4,4-TETRAMETHYL-l, 3-CYCLOBUTANEDITHIONE , THE IMINE OF 2,2,4,4-TETRAMETHYL-l,3-CYCLOBUTANEDIONE , l,3-DIPTHENYL- 2-PROPANONE , 1,3-DIPHENYL-2-PROPANETHIONE, AND THE IMINE OF 1,3-DIPHENYL-2-PROPANONE.

Compound Proton Chemical Shift (ppm)

b.4l 42 Single.t at 1.40 (cc14) ,

d Singlet at 3.59 (CC14) Multiplet at 7.12 (CC14)

e,40 Singlet at 4.17 (CC1 4 ) Multiplet at 7. 19 (CC14) 19

TABLE 9. Continued.

Compound Proton Chemical Shift ppn ( )

f Multiplet at 1.00 CC14 Multiplet at 1.45 ( CC1 ) ( 4 ) Singlet at 3. 62 CCl4 Multiplet at 7.18( CX:l) 4 ( )

d aSee spectra page 56. see spectra page 53, experimental page 39. e bsee experimental pages 41,42. see experimental pages 39-41. csee experimental page 43 f see spectra page 54 , experimental page 43.

TABLE 10. PROTON CHEMICAL SHIFT OF tv1ETHYLENE HALIDES 30 I . -CH2-X , X = F, Cl, Br, ( )

Methylene Halide Chemical Shift (o )

4. 50

3.44 3.40 3. 15 20

TABLE 11. ELECTRONEGATIVITY OF HALCX3EN ELEMENTs.31

Element Electronegativity

F 4.0

Cl 3.0

Br 2.s

I 2.5

c.() ...._ 6 4. 4. 50

+l 4.4 IC'" 4-4 •rt ..c.--t CJ)

E Q) ..c 3.8 u c: 3.6 0 3.40 3.44 +l .,... 0 H 3 0.. .4 ,3!115\ 3.2

3.0 2.0 2.5 2.s 3.0 3.5 4.0 Electronegativity vs. the Figure 2. Proton chemical shifts of methylene electronegativity of halogen elements. 21

32 TABLE 12. PROTON CHEMICAL SHIFT OF METHYL HALIDEs.

Compound Chemical Shift (5)

4.26 3.05

CH3-Br 2.68 2.16

�4.26 4.0

r-i co () •r-t r 3.05 3.0 1!E

0 ·68 c: 0 c} +' 0 H p..

2.16 14"'" 2.0 . 2.5 2.s. 3.0 3.5 4.0 Electronegativity

Figure 3. Proton chemical shifts of methyl halides vs. the electronegativity of halogen elements. 22

1.4 .el.40 '

.-1 co () •rl

E Q) at" 1.30 l · 3 ..c u c::: 0 +' 0 H 0..

1.23 ,.., � .�

Figure 4. Comparison of chemical shifts of methyl hydrogens of 2,2,4,4-tetramethyl-l , 3-cyclobutanedione , 2,2,4,4- tetramethyl-l,3-cyclobutanedithione and trans-N ,N' dicycloheptyl-2,2,4,4-tetramethyl-l,3-cyclobutanediimine. 23

4 5 •.

.. Q) 4-4 •rl 4.17 +' c:: O'l � ..c: 0 Cf) H '"OQ) 4.0 ...... > .�Q)co ::r::Q)

E c:: ..c: ...... u >- ..c: .sc:: �+>

0 H 4r3.62 0...... 3 .59 3.5 ,

Figure 5. Comparison of chemical shifts of methylene hydrogens of 1,3-diphenyl-2-propanone, 1,3-diphenyl-2- propanethione, and N-n-butyl-1,3-diphenyl-2- propaneimine . 24

Electronic Spectroscopy

TABLE 13. ELECTRONIC SPECTRA OF l,3-DIPHENYL-2-PROPANETHIONE33 AND 2,2,4,4-TETRAMETHYL-l,3-CYCLOBUTANEDITHIONE41

Compound Absorptions

s 510 EtOH, 10 33,a ( e ) II 33 c 522 Cyclohexane,< 10 ( e ) CH I\ CH < I '\ ¢ ¢

. 41 b s= =s 500 22.4, hexane ' 298(e 409, hexane) 227 (e 21, 600, hexane) Q (e )

asee experimental page 41. bsee experimental page 42.

Mass Spectra

Upon standing, a white solid was found to precipitate from solutions of 1, 3-Diphenyl-2-Propanthione. Proof that the material was a dimer was obtained from the mass spectrum which gave a molecular ion at m e 452. The exact structure could be obtained from the examination of / 34 the ultraviolet and nmr spectra and elemental analysis XXXIV . ( )

XXXIV ( ) 25

TABLE 14. MA.SS SPECTRA44 OF 2,2,4,4-TETRAMETHYL-l,3 -CYCLOBUTANEDIONE , 2,2,4,4-TETRAMETHYL-l , 3-CYCLOBUTANEDITHIONE , THE !MINE OF 2,2,4,4-TETRAMETI-NL-l , 3-CYCLOBUTANEDIONE.

A Intensity of Mole- B Intensity of ( ) .+- ( ) Compound cular I on M • Fragmentation o,s,N- A W-·-c =x(x = ) /.

O= =O 8.0 2.0 0.25 Q mm mm s- =s 15.4 5.5 0.36 Q mm mm ,...c7H13 N 76. 0 13. 0 0.17 1 = =N C7H13 Q mm mm 45 TABLE 15. MA.SS SPECTRA OF 1,3-DIPHENYL-2-PROPANONE , 1,3-DIPHENYL-2- PROPANETHIONE, AND THE IMINE OF 1,3-DIPHENYL-2-PROPANONE.

B Intensity of (A Intensity of Mole- ( ) Compound ) Fragmentation cular Ion M+ • -C H -CH W .. 6 5 2 • % 0 a 17 .o 2. 12 c 4.8 CH/2 ,CH � mm JTUT\ C6H/5 C6H5 s JI 13.7 68. 8 5. 03 CH,,,,c, CH / 2 2 mm mm C . 6H5 " C6H5 26

TABLE 15. Continued.

A Intensity of Mole B Intensity of Compound ( Fragmentation) ( ) cular Ion M+• ·-c6H5-CH2· w

6.5 mm 24.5 mm

Melting Point

TABLE 16. MELTING POINT OF 2,2,4, 4-TETRAMETHYL-l, 3-CYCLOBUTANEDIONE, 2,2,4,4-TETRAMETHYL-l, 3-CYCLOBUTANEDITHIONE,_THE IMINE OF 2, 2, 4, 4-TETRAMETHYL-l, 3-CYCLOBUTANEDIONE.

Compound Melting Point °C ( )

112-114a 0= 9 =0

123. -125b, 4l,42 s= S) =s �

127-128c,43 asee experimental page 39 b see experimental pages 41-42. csee experimental page 43. DISCUSSION

From the dipole moment data Table 5) one can see that since ( oxygen has a higher electronegativity than sulfur, the water molecule

will have a larger dipole moment than.that of the hydrogen sulfide

molecule in the cr-bond system. However, the dipole moment of carbon

monosulfide is about 15 times larger than the dipole moment of carbon monoxide. This polarization is due to the greater electron demand

of the sulfur atom than the electron demand of the oxygen atom in the TT-system. But when one checks the dipole moments Table 5) ( obtained from the microwave spectroscopy ,29 it shows an opposite phe

nomenon. The only apparent explanation the author can surmise to ex

plain this is that the experimental data for thioformaldehyde is in error. Thioformaldehyde is very unstable and tends to polymerize read

ily. It has only been identified by microwave spectroscopy and perhaps

the experimental data is ·a result of a mixture of. compounds. If the data is correct, then the only alternative is that dipole moment studies

can not be used to describe the polar nature of the TT-bond in these simple chromophoric systems. If one looks over the force constants

Table 7) calculated from ir frequencies Table 6) of different uncon ( ( jugated ketones, thiones and imines, it appears that the double-bond character between the carbon and sulfur atoms is less than the double bond character between carbon and oxygen atoms or carbon and nitrogen atoms. 28

This phenomenon is eas ier to see· when one observes the bond dis

tances obta ined from X-ray study Table 8). It is known that the ( 0 double-bond distance between two carbon atoms is 1.34 A; from Figure 1 it is reasonable to say that since the double bonds between carbon

and oxygen atoms or carbon and nitrogen atoms are more sta ble shorter ( bond distances than the double-bond between carbon and sulfur atoms , ) the latter is more easily broken or removed. / In the nmr experiment, energy is absorbed by the proton nuclei

of the molecules at a certain frequency when a magnetic field H0 is

provided in the gap of the electromagnet Figure 6). (

Figure 6. Energy diagram for

nmr. 29

Actually, the effective field H at the hydrogen nucleus is eff smaller than H0 , the ma gnetic field provided by the instrument . The

electrons in the vic inity of the nu cleus tend to shield it from the

perturbation by the appl ied field. They will circulate so as to pro-

duce an electrical current and hence a magnetic field , reacting

aga inst the applied directing field H0 Figure 7), so the (

H = H l-a , where is called the shield ing constant . This genera l eff ( ) property of ma tter isa ca l led Q.iama gnet ism.

--��- nu cleus

r------circulating electrons

. magnetic line of f rce � � Figure Diamagnetic sh ielding of nucleus by circulating 7. electrons .

The degree of shielding depends on the density of the circula ting

electrons, and as a first , very rough approximation, the degree of

shielding of a proton on a carbon a tom will depend on the inductive

effect of other groups atta ched to the carbon atom Figure 8). These ( 30

are small effects ; on the order of parts per million (i.e., cycles

per second) in relation to a standard ·reference (TMS). The difference

in the absorption position of a particular proton from the absorption

position of a reference proton is called the chemical shift of the particular proton.

Figure 8. Perturbation of electron cloud around a proton by inductive withdrawal by an electronegative substituent tx).

The argument will be as follows. Around protons the electron distributions are almost spherical. Any electrostatic distortion of these ls orbitals drawing electron density away from the nuclei should and does reduce their shielding (Figure 8). In other words, it is possible to understand these particular sequences of chemical shifts toward lower energy or to the left side of the nrnr spectra with increasing electronegativities of different substituents (see Tables 10-12,

Figures 2, 3). 31

From a comparison of chemical shifts of the methyl .protons of

2,2,4, 4-Tetramethyl-l , 3-Cyclobutanedione and its analogues Table 9). ( Figure 4); it is obvious that the methyls of the thione have the ( largest shift value. This data shows that the thiocarbonyl group has the strongest electronegativity (XXXV) which is perhaps chiefly due to a positive inductive effect +I , and suggests there ought to be a ( )

6 + 6 = c s ) (XXXVI) charge distribution (XXXVI) between the carbon atom and the sulphur atom , which is greater than the charge distributions of the carbonyl group (XXXVII) and the imino analogue (XXXVIII). .

6+ 6- 6 + 6 - = C = N c 0 > (XXXVII) >(XXX VIII)

The comparison among 1,3-Diphenyl-2-Propanone and its analogues

Figure 5 shows a similar phenomenon . The chemical shift of the ( ) methylene hydrogen of the thione has the largest chemical shift value.

Nuclear magnetic resonanse data supports the fact that an unconju gated thiocarbonyl chromophore possesses the strongest polarized char acter when compared to the carbon and nitrogen analogues. The valence electrons35 in carbon, oxygen and nitrogen are in the second shell and may be considered to utilize four orbitals one s and ( 32

three p , ind ividually or in various hybr idized combina tions . Each ) orbita l has a node , the 2s node being a spherical contour , the three

2 p orbita ls ea ch having one of three mutually perpendicular planes

as nodes Figure 9) . ( y y

2 PY y 3 y PY x � x 3 Ufbdxy Figure 9. Representa tive atomic orbita ls.

The va lence electrons in su lfur occupy the third shell, which ma y be considered to have a total of nine orbita ls available one s, three ( p, and five d orbita ls , ea ch with two nodes. The 3 s nodes are two ) concentric spheri�a l contours . The 3 py nodes are the xz-plane and a n axially symmetr ical py contour Figure 9). Similar nodes exist for 3 ( the 3px and 3p2 orbitals. If two of the 3 p orbitals ha ve axes as indicated in Figure one possible orbita l may be represented as 10, 3d 33

indicated. There will be an additional 3p2 orbital perpendicular to

the xy-plane. There will also be a 3dxy orbital with four lobes in the

xz-pla ne and a 3dyz orbita l with four lobes in the yz-plane.

3 PY© 3 dxy 3 dxy G © 3 px --��--3 px 8 EB 3 3 dxy G

3 e PY Figure 10. Va lence electron orbita ls of the sulfur atom.

Suppose one locates two nuclei bearing 2 py orbita ls along the x-axis , as in Figure 11; it can be seen tha t overlap of orbita ls will occur area s of the same sign. The favorable interaction resu lting in is referred to as n-bonding . If one of the p orbitals is a 3 py

y y

Figure 11. A 2p-2p n-bond. 34 orbital., the overlap will soon involve some antibonding interactions

(Figure 12), son-bonds from 2p and 3p orbitals will be less favorable than from two 2p orbitals. 47 This can be detected from ir frequencies and bond distances from x-ray data.

y y

Figure 12. 2p-3p n�bond. A

As a 2py and a 3dxy orbital approach each other along the x-axis, bonding overlap may occur, 48 as indicated in Figure 13.

y y

Figure 13. A 2p-3d bond. 35

Since the 3d orbitals in sulfur are unoccupied , the bonding electrons must come from the 2p orbital to the vacant 3d orbital on sulfur. The result is a polarized n-bond and this reason could ex- plain the chemical shifts of the and hydrogens in compounds con- 13 taining the thiocarbonyl group. Q'

The experimental data from electronic absorption spectra and symmetry arguments 38 ,39,46 suggest that the sulfur atom in thiones is·best represented as nonhyb�idizedo This means that there are undistorted 3p and 3d orbitals and such a consistent geometry of these orbitals is due to the use of the 3d orbital to overlap with the 2p orbital of the carbon atom (Figure 14) .

y y

> , and 2p-3d igure 14. A sp2 3p a-bond, partial 2p-3p n-bond partial p· - n-bond. 36

Katritzky suggested a duel mechanism for the dimerization. 36 The ionic mechanism may be due to the polarization of the thio carbonyl group as in Figure 15.

Figure 15. Ionic mechanism of dimerization of two thiocarbonyl groups .

A comparison of the mass spectra of unconjugated thioketones with those of unconjugated ketones and azomethines indicates that the major fragmentations of all three classes of compounds are the same . The stability of specific fragments with respect to their molecular ions 50 differ. Fragments containing the C = S moiety can stabilize a ) positive charge to a greater extent than those containing C = and > O

C = groups Tables 14 and 15) when compared to the intensities ) N_. ( of their respective molecule ions. This suggests that a large ionic contribution occurs in the resonance hybrid of thioacyl ions and it appears that this procedure may be used in studying the ground states of molecules containing the title substituent.44 In any event , the mass spectral data may be used ernperically to determine the structure of compounds containing the chromophores examined. Mel ting points may serve as a rough guide to the degree of nonpolar character of similar compounds, and covalent substances generally have 37

low melting points .45 From Table one can see that the thiocarbonyl 16 compound has more polar chara cter than the carbonyl compound . The bisimine ha s two bulky substituents on nitrogen atoms, so the melting point comparison is not va lid. CONCLUSIONS

According to the above data, one can see that 2p-3p rr-bonds are less stable than 2p-2p rr.-bonds and that some sort of bonding donation of electrons from 2p orbitals into at least certain of the vacant 3d orbitals on sulfur can occur; which supports the hypothesis that the thiocarbonyl chromophore has more ionic contribution to the resonance hybrid than those of carbonyl and·imine chromophores.

This is not predictable the basis of the electronegativity on of the heteroatoms. EXPERIMENTAL

Description of Instrurnenta tion Used

Infrared spectra were run on either the Perkin-Elmer 521 grating

Infrared Spectrophotometer or the Perkin-Elmer 700 Infra�ed Spectro meter. Samples were run neat , as nujol mulls, or as KBr pellets .

KBr pellets were prepared on a Carver Laboratory Press Model B. Visible and ultraviolet spectra were run on a Beckman ratio DK-2A recording spectrophotometer. Samples were run in silica cells as dilute soluti�ns in cyclohexane or in 95 percent alcohol.

Nuclear magnetic resonance spectra were obtained by use of a Varian A-60A analytical nmr spectrometer . Samples were run as solu

tions in cc14• Mass spectra were run on the Finnigan 3000 GC/MS system .

The experimental work was performed at South Da.kota State Uni versity, Brookings , South Dakota. Melting points were obtained by

using a Thiele tube containing paraffin oil and are uncorrected.

Compound (XXVIII) was made by Eastman Organic Chemicals and compound (XXXI) was made by Aldrich Chemical Co. , Inc.

Preparation of Diethyl ketals Ketals were prepared by a modified procedure described by Hurd and Pollack 37 and by Nichols . 38 A mixture of 63 g (0.3 mole) of ketone, 44 g (0. 3 mole) triethylorthoformate , 0. 05 p-toluenesulfonic 9 40

acid, and 150 ml of dry ethanol in a 500 ml flask was refluxed 48

hours. The mixture was then cooled to room temperature and neutralized

with sodium ethoxide. To this was added 500 ml of water and the organic

layer was washed twice with 50 ml portions of water and then dried

over anhydrous potassium carbonate. The material was then filtered to

remove the potassium carbonate and then immediately distilled.

2,2-Diethoxy-1,3-diphenylpropane

Prepared as described by·Nichols.38 The product was obtained ° in 38 percent yield, bp14 200-207 C. The infrared spectrum,

neat on sodium chloride plates,mm showed the following absorptions: 3010, 3960, 3890, 1940, 1870, 1790, 1710 (weak), 1640, 1595, 1490, 1440,

1370, 1355, 1220, 1157 (broad), 1110, 1075, 1043, 1030, 945, 909, 852, -1 800, 747, 727, and 695 cm ). The nrnr spectrum in CC14 had the fol lowing signals: 1.25 (6H, triplet), 2.85 (4H, singlet), 3.66 0 5 0 (4H, quartet), 7.196 (lOH, multiplet).

Preparation of Thiones

Thiones were prepared from a procedure patterned after the method . of Mayer and Berthold39 and Nichols.40 To o.l mole of the ketal, in

a 20.3 cm test tube, was added 0.05 g of p-toluenesulfonic acid as

a catalyst. Hydrogen sulfide was introduced into this solution until it was bright red. The solution was then distilled at reduced pres sure or was used as such for spectroscopic studies. 41

40 l,3-Diphenyl-2-propanthione (XXXII)

The visible spectrum in cyclohexane gave an- absorption at 510 nm

10 . The nmr spectrum in CCl4 had the following signals: 4.17 6 (€ ) 4H<, singlet , 7.19 6 lOH, multiplet . The mas s spectrum gave a ( ) ( "' ) molecular ion at m e 226 and had a p 2 peak at m e 228 which was / / 10.2 percent of the parent peak. The+ boiling point and yield were not

determined.

Preparation of Tetramethyl-1,3-ciyclobutanedithione (XXIX} This compound was prepared by a modified proc,edure described by 1 Elam and Davis4 and Shen.42 A solution of 30 g 0.21 mole of ( ) tetramethyl-1,3-cyclobutanedione in 100 ml of pyridine was stirred

and refluxed with 45.4 g of phosphorus pentasulfide for 1.5 hours.

The mixture was cooled and the liquid was decanted. The residue was

extracted by heating it with two 20 ml portions of pyridine at reflux-

ing temperature. The combined pyridine solutions were distilled rapidly through a Vigreux column at reduced pressure until most of the pyridine had been removed from the mixture and a solid material

appeared in the columne The residue was taken up in hot - methanol, and the solution was decanted from a small amount of insoluble material. The distillat·e was combined with the methanol extract of the residue , and the pyridine and the methanol were removed by fraction ation through a vacuum-jacketed column until no liquid came out. The distillation residue was cooled to room temperature and filtered. One recrysta the product from methanol gave g 21 percent llization of 7.6 ( ) 42

of crude product. Repeated recrystallizations from methanol yielded a ° sample: mp 123-125 , nmr spectrum (CC14), singlet at 1.40 ppm ; infrared absorptions at 1460, 1265 , and 107q cm-1; uv absorption at hexane 227 hexane A. mu 21, 600), 298 mu 409), and a weak peak at A. �x (e (e �x 500 mu 22. 4). Major peaks in the mass spectrum were at m/e 86 (e (100 percent) , 71 (54.4 percent) , 96 (52.9 percent) , 81 (50.8 percent) ,

45 (48.4 percent), and 39 (21.8 percent). The parent peak was at m e / 72.

Preparation of N,N' -Dicycloheptyl-2,2,4,4-tetramethyl-l,3- cyclobutanediimine

The procedure was described by Schmidt43 (X:XX). Into a 500 ml flask fitted with a Dean-Stark trap were placed 2,2,4,4-tetramethyl- cyclobutanedione , 50.00 g (0.357 mole) ; . cycloheptylamine, 83.60 g (0.738 mole); p-toluenesulfonic acid monohydrate, 4.17 g (0.025 mole); and 200 ml of toluen·e. The mixture was allowed to reflux for several days until it appeared no more water was being collected in the Dean-Stark trap. Between 6. 2 ml and 7.2 ml of water were collected. The yellow solution was then allowed to stand for several days until crystallization ceased. The mixture was filtered with suction, giving white crystals and a yellow filtrate. The white crystals were recrystallized from aqueous ethanol giving 12.36 g of solid, m.p. 127-128 °. The solid was dried in a vacuum oven and then in an "Abderhalen dryer over toluene and P205. The bisimine structure 43

was confirmed by uv , nmr, and ir spectroscopy. The nmr spectrum gave 64.62(s, impurity), 53.50 (m , 2H) , 51.54(s, 24H, -cycloheptyl), 5 1.39

(s, cis-CH3), &l.23(s , trans-CH3), 51.12(s, cis-CH3). The infrared spectrum of a nujol mull gave bands at 1670, 1360, 1180 , and 1065 cm-1.

Anal. Cal 'd for C22H38N2: C, 79.94; H, 11. 59. Found: C, 78.44; H, 11.23.

Preparation of the N-n-butyl lmine of 1,3-diphenyl-2- propanone (XXXIII)

Into a 250 ml ·flask fitted with a Dean-Stark trap were placed

1, 3-Diphenyl acetone 8.35 g (0 . 040 mole.); n-butyl amine 3.98 g (0.055 mole); p-toluene sul fonic acid monohydrate 0.03 g and 75 ml of toluene. The mixture was allowed to reflux for two days until the approximate theoretical yield (0.04 mole,· 0.72 g) of water was collected. The hot solution was distilled rapidly through a Vigreux column at reduced pressure (30 ""-'20 until no liquid could be ) collected. The residue was a viscousmm high boiling. liquid (maybe a liquid crystal); it could not be purified further. The nmr spectrum in CC14 had the following signals: 1.00 6 and 1.46 & ( 9H, multiplet), 3.6 2 ( 4H, singlet), 7 .19 ( lOH, multiplet). The ir spectrum in CCl 0 0 4 showed the following absorptions : 2275 , 1685, 1600, 1590 , 1520 , 1300, 1220 , 1160 cm-1. There was a molecular ion (m/e 265) in the mass spectrum and the fragmentation pattern was consistent with the structure. 44

REFERENCES

L ttr inghaus , A. and J. Chohrnann. Na L turforsch, lOb, 365(1955); u See Ref. p. 2340. z. 3, 2. LUttringhaus , A., R. Mecke and J. Gro�rann. Elektronentheorie der Homo-opolaren Bindung , p. 152, Akadernie-Verlag, Berlin (1956) ; See Ref. 3, p. 2340.

3. Janssen , .M. J. and J. Sandstrom. "Charge Distributions in Car bonyl and Thiocarbonyl Compounds ," Tetrahedron, Vol . 20 , ( 1964) , pp. 2399-2349.

4. Wa lsh, A. D. Trans . Faraday Soc., 43 , 158 (1947); See Ref. 3, p. 2339.

5. Vilesov, F. I. Dokl . Acad. Nauk SSSR, 132(1960); See Ref. 3, 2339. P· 6. Vilesov, F. I. and B. L. Kruba tov. Ibid., 140, 1364(1961); See Ref. 2339. 3, P· Janssen, The electronic structure of organic thicne 7. poundsM. , J.Thes is , Utrecht (1959); See Ref. 3, 2340. p. corr: 8. Janssen, M. J. Rec . Trav. Chim ., 79, 1066( 1960); See Ref. 3, p. 2340 .

9. Streitwieser, A., Jr . and P. M. Nair. Tetrahedron, 149(1959); See Ref. 3, p. 2340. �'

17 , 10. Wheland , and D. E. Mann . J. Chern . Phys . • , 264( 1949); See G.Re f.w. 3, p. 2340. ll. Robinson , J. Chem. Phys., 21 , 1741( 1953); See Ref. 3, p. 2349G.. w .

ing . J Amer. Chem . , 12. Brockway, L. O., J. Y. Beach and L. Paul • Soc. 57, 2693 (1935); See Ref. 2349. . 3, P· 13. Kimura , and M . Aoki . Bul l. Chern . Soc . , Japan, 26, 429 (1953); SeeM. Ref . 3, p. 2349.

997 ( 1960); See Ref. 2349. 14. Truter , R. J . Chem. Soc., P· M. 3 , 15. Vaugha n, P. and Donohur . Acta . Cryst ., 539 (1952); See Ref. 2349. J. �' 3, p. 45

16. Kunchur, N. R. and M. R. Truter . �J_. _C_h� e�rr �1 .__;;;S�o�c�. , 2551(1958); See Ref. 3, p. 2349.

17. Jensen, K. A. Acta Chem . Scand. , 17, 551 (1963) ; See Ref. 3, 2349. P· 18 . Janssen, M. J. Rec . Trav. Chim. , 83 , 931-940, (1963); See Ref. 3, p. 2340.

19. Stewart, R. and L. J. Muenster. Can. J. Che 1. , 39, 401 (1961). � 20. Kutze ln igg, W. and R. Mecke . Spectrochirn . Acta . , 17, 539 ( 1961) ; Ber. , 94, 1706 ( 1 961).

21. Janssen, M. J. Spectrocbirn . Acta., 17, 475 ( 1961).

22 . Katritzky, A. R. and R. A; Y. Jones . Chem . and Ind. , 722(1961).

23. McClellan, A. L. "Tables of Experimenta l Dipole Moments", w. H. Freeman and Company, (1963) , 48. p. 24. Ibid. , 579. p. 25. Ibid., p. 41.

26. Friedlander, P. H. and J. Monteath Robertson .· J. Chem. Soc., 3083 ( 1956) •

27. Shirrel , Charles D. arid Donald E. Williams . Acta . Cryst. , B29 , 1648 ( 1973) •

28. Jensen, P . Department of Chemistry, South Dakota State Uni versw.it y, persona l conununication .

29. Johnson , Dona ld R. , Francis Powell and William H. Kirchhoff, x. J. Mol . Spec ., 39, 136-145(1971).

30. Silverstein, R. and Ba ssler. "Spectrometr ic Identification of G. Organic Compounds ," 2nd Edition , John Wiley and Sons, Inc. , . New York , 1968 , 137. P · 31 · Any Period ic Ta ble. Harper and Row 32. Laszlo, P. a nd P. Stand. "Organic Spectroscopy ," p ' • • ( 1 971 ) 50 46

33. Nichols , P. Department of Chemistry , South Dakota State Univer sity, Thesis , (1970), pp. 17-19. 34. Ibid. , p. 30 .

35. Price , C. and S. Oae. " Sulfur Bonding ," Chapter One , The Ronald Press Company, New York , 1962.

36. Katritzley, A. R., R. Mayer , J. Morgenstern and M. J. Sewell . J. Chem . Soc., 5953( 1965 ) .

37. Hurd , C. D. and M. A. Pollack . J. Am . Chem . Soc., 60 , 1905(1938). 38. Nichols, P. Department of Chemistry, South Dakota State Univer ity , M. S. Thesis , (1970) , p. 35.

39. Mayers, R. and H. Berthold, Ber. , 96, 3096(1963) . 40. Nichols, P. Department of Chemistry, South Dakota State Univer sity, M. Thesis , (1970), p. 37. s. 41. Elam, E. U. and H. E. Davis. J. Org. Chem., 32, 1562(1967).

42. Shen , M. Department of Chemistry, South Dakota State University, M. Thesis, (1972), p. 32 . s. 43 . Schmidt, E.. Department of Chemistry, South Dakota State Univer sity, Ph.D. Thesis , (1973), 32. p. 44. Worman, J. J. and J .. Y. Lee .. Ninth Midwest ACS Meeting , Lawrence, Kansas .

45. Douglas, B. E. and D. H .. McDaniel. "Concepts and Models of In organic Chemistry ," Blaisdell Publishing Company, First Edition, (1965 ) , P• 89 ..

46. Ibid. , P · 63.

47. Ibid. , P• 58. 48. Ibid., 59. p. 49. Janssen, M. J. Rec. Trav. Chim. , 81, 650(1962) .

50. Budzikiewicz , H., Djerassi and D. H. Williams. "Mass Spectro c. 67) , metry of Organic Compounds, " Holden-Day, Inc .,_ (19 PP· 34-36. NO.

001-1061. ,..,u:1;,1

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