JOURNAL OF RESEARCH of the National Bureau of Standards-A. Physics and Chemistry Vol. 67A, No. 2, March- April 1963 Cyclic Polyhydroxy Ketones. 1. Oxidation Products of Hexahydroxybenzene (Benzenehexol)
Alexander J. Fatiadi, Horace S. Isbell, and William F. Sager*
(D ecember 11 , 1962)
R eliable procedures are given for the preparation and purification of hexahydroxy I ~ benzene (benzenehexol), tetrahydroxy-p-benzoquinone, rhodizonic acid, triqllinoyl (cyclo hexanehexone), croconic acid, a nd lellcon ic acid (cyclopcntanepentone). Certain derivatives and color tests, as well as infrared and ultraviolet spectra, are reported for t heir idcntification.
I. Introduction Hexahydroxybenzene (benzenehexol, I ) can be prepared from inositols (cyclohexanehexols) and from On oxidation, cyclohexanchcxols (inositols) yield tetrahydroxy-p-benzoquinone (II, obtained by self l;:eto derivatives which, by successive enolization and condensation of glyoxal in alkaline solution). Oxi elimina t ion reactions, can b e transformed to poly dation of I yields II, which is further oxidized to hydroxybenzenes [1 - 5).1 ] n progressing from cyclo rhodizonic acid (III), and this is oxidized to tri hexane derivatives through cyclic olefinic intermedi quinoyl (cyclohexanehexone, IV). T etrahydroxy ates to fll"om ati c compounds, reactions and materials p-benzoquinone ftnd rhodizollic acid are not only are encountered which are eminently suited for the interesting in their own right, but also serve as 1..... I s tudy of reaction mechan isms and basic concrpts of intermediates in the preparation of croconic acid ), theoretical orgfln ic cl lemistry r6] . (V) , a clihyclroxy t riketon e having fl five-carbon ring. Oxidation of crocon ic acid yields leuconic acid (VI). B ecause these compounds, needed as Oil o model substraLes in a stud y of antioxidant and oxygen-carrier properties, were noL available in fl 1."-1)- 0" I IO -~I'I-- on suitable state of purity, the methods reported in the L o ll experim ell tal part were developed for their synthesis JIO-V-Oll JI O-V and purification . 6n 8 11 2. Hexahydroxybenzene (Benzenehexol/ I) [7] J I exall ydroxybenzene 'f etrahydroxy·p·benzoq uinonc (Benzenehexol) 2.1. Discussion o o Hexahydroxybenzene (I ), the enolic form of the trihydroxytriketocyclohexanes, can be prepared by 0=0=- II I on the self-condensation of potassium carbonyl followed 0- - on by hydrolysis [8 , 9], by nitration of di-O-acetylhy :~:: droquinone followed by reduction and hydrolysis I o [10], by oxidation of myo-inositol followed by enoli In IV zation [11], and by reduction of tetrahydroxy-p benzoquinone (II) by means of stannous chloride Rllodizonic acid 'l'riquinoyl (Cyclollexa nebexon e) [12] . o O =~~= o 2.2 Preparation of Hexahydroxybenzene [13]2 O~
• 2 This procedure was developed in 1959 by one of us (A.J .F .) , under tbe direc- • Tbe George Washington UniverSity, Wasbington, D . C. tlOn of Dr. William F: Sager at George Washington Unil'ersity [13], and was 1 Figures in brackets indicate the literature references at tbe end of this paper. bneft y descnbed by I
L __ l~ chloric acid to give lustro Ll s, dark crystals [8] ; rcmove all colored impurities. The crystalline ( alternatively, it may be recrys Lallized from acetone residue, consistin g or sodium chloride and crude > by the addition of petroleum ether Lo give small , rhodizonic acid dih ydrate, is air-dried and pulverized, I dark crystals. Spectrograms arc given on pages 1.'58 and the powder is add ed to 200 ml of dioxane pre lm el ] 60. heated to 80 °C. The suspension is stirred for 5 min and then filtered through a fill er pl1per prccoated 4. Rhodizonic Acid (III) [21] wi th decolorizing carbon. The in soluble mft tier is washed with 50 ml of warm dioxane, and t]IC sli ghtly 4.1. Disc ussion colored fil trate is cooled to about 20 °C. Pentane (about 150 m1) is add ed to incipient Lurbidit.y, a ile! Heretofore, rhodizonic acid (III), the oAidation crvstallization of rhoclizo nic acid dihydraLe is in product of II, has been prepared by oxidation of duccd by scratching Lhe illside walls of t he container myo-inositol with nitric acid [11], b~ ' reduction ammonium. rhodizonltte [2 1] fro lll glyoxal, of dioxane 11l1d pen ta, ne, ftnd air-dried ; wt, 25 to 35 g. and or rhodizonic ac id from th e cl isoclium salt of The crud e r hod izonic acid dihydra t e is recrystal II by oxidation in air. lized from warm dioxflne by the addi tion of pentane alld ether ; by concentration of the filtrate, an ft ddi 4.2. Preparation of Tetrahydroxy-p-benzoquinone tional crop is obtai ned. The air-dried product, and Ammonium Rhodizonat9 from G lyoxal which still contains dioxane, is dried for 48 hr in a, vacuum desiccaLor over sulfuric acid; toLal yield , Aqueous glyox'll (6 00 g or a :3 0-pe]'cen.t solution) about 21 g (60%) of colorless crysLals. :VfeRsli rem ents is seH-condensed in the presence of sod lUn l sulfLte, of infrHred Hnd ultraviolet absorption are reported !; oxygen, and sodium bicarbonflte as described in Oll pages 158 Hnd 160. section 3.2. After 1 hr of aeration, 100 g f sodilLlll The pmily of the product may b e delermined b.r hydroxide is added. The lllkniin e solution (ZJH ]0 ) titration with iodin c [20]; 155 mg of l"llOdizonJ c is' heated, with aeTation, to in cipi ent boilin g, and acid diJ rHlraLe co nsum e 14.97 ml of O.l -N 13 solu cooled to room temperature. Tll e mixture of tion ; founCl , 15.07 ml. I crystallin e sod ium salts of II and III is filL ered off If subjected to a high vacuum (0.1 mm) at room r· (uid washed successively with 50 ml of cold, 50- temperature thc compound is converted into thc I percent aqu eo us methanol ft nd 50 III 1 of methanol. sC(l rlcL-l"ed crysLals 0(" anhydrous rhodizoni c acid in as The air-dried sfl lLs (24 to 26 g) In·e cl issol ved in little as 5 min. The same Lransform ation can be 200 ml of 2.5-N hydrochloric eLcid b.\' boilin g, allcl acco mplished at higher tcmperatures by vacuum. the solu tion is immediately cooled in ice .4 T he subli mation [20]. Rhodizonic acid gi ves a colorless resul ting crystallin e II (8 Lo 9 g) is se pamted by soluLion in 2.o5-N hydrochloric acid, wh ereas tetrn filtration, washed \vith 20 ml of icc water, an(l dried . hydroxy-p-benzoquinone gives a cherry-rcd solution. The ice-cold, dark-red filtrate is brought to pH 5.5 to 6.5 wiLh flllllllo nin. The r c"ul ti ,g, dluk blu e, crystalline ammonium rl lOdizo nn Le is se parated 5. Triquinoyl (Cyclohexanehexone, IV) [23] by filtratioD, waf'llcd wi th 25 ml or ice WeLL er, and 5.1. Discussion (" Ilir-clried ; wt, 7 to R g. Tl is recr.ysLallizecl fro m 750 ml of hot water. In 1862, Lerch [24] obtained a product, now known as triquinoyl, by oxidaLion of either hexahydroxy 4 .3. Preparation of Rhodizonic Acid from the benzene (I ) or tetrahydroxy-p-benzoquinone (H ) with Disodium Salt of II nitric acid or chlorine. The substflnce has been characterized by Nietzki and coworkers [8 , 10, 25], The di sodi um salt of II (40 g), prepared as described and studied by H enle [26], Bel'gel [27], and Eistert in section 3.2 , is placed in a large, fiat-botLo med dish and coworkers [20, 22] . The procedure described and hp,ated in an oven at 170 to 180 °C for 24 hr. here is based on the original work of Lerch flnd of The residue is suspended, with mechanical stirring, Nietzki. Because some workers have experienced
I. in 200 ml of warm, 2.5-Nhydrochloric acid, and after difficulty in the preparation and purification of IV, several minutes, 1 g of decolorizing carbon is added; the procedures are given in detail. ,' . t he solution is cooled in ice and filtered through 5.2. Preparation of Triquinoyl Octahydrate 'I a filter paper precoated with paper pulp. The . -1 brownish-yellow solution is concentrated under R ecrystallized tetrahydroxy-p-benzoquinone (10 g) I diminisbed pressme at 35°C to a semicrystalline is added in small increments during 5 min to a me mass, and the aq ueous hydrochloric acid is removed chanically stirred solution of 100 ml of concentraten by successive addi tion and evaporation of three nitric acid and 205 illl of water kept at 10 °C. The o5 O-ml portions of a 1: 1 mixture oJ benzene and reaction is continued Jor an additional 5 min , 25 ml " acetone. The residue is triturated with 50 ml of of water is added, and the mixture is cooled in ice ~, acetone, the suspellEion is filtered, and the in soluble for 15 min. The crystalline triquinoyl octahydrate producL is wasbed witb suffi cient cold acetone to t hat separates is filtered off, washed successively 'Prolonged heating causes disproportion ation [22] . with 20 ml of ice watOL" and 30 ml of fin ice-cold ,
155 1: 1 mixture of acetone and ether, and air-dried; min, the m anganese dioxide is filtered off, thoroughly wt, 12 to 12.5 g; mp 96 to 97 °0. washed with water, fLnd driedlat 150 to 160°C for The substance is recrystallized in the following 18 to 24 hr. After its recovery from reaction mix manner: The octahydrfLte (5 g) is suspended in 50 ml tures, active manganese dioxide can be used of methanol containing 3 ml of concentrated nitric repeatedly if it is redried at 150 to 160 °0 for 18 to acid, and the suspension is heated to 55 to 60 °0, 24 hr. Manganese dioxide prepared by other with stirring. When dissolution is complete, about methods proved to be less satisfactory. 200 mg of decolorizing carbon is added, the suspen sion is filtered, and the insoluble matter is washed 6 .3. Barium Croconate Hydrate with 25 ml of water. The combined filtrate and washings are evaporated under diminished pressure To a solution of 40 g of sodium hydroxide in 1.2 to about 25 ml, and the solution is cooled in ice liters of water arc added, with stirring, 21 g (0.1 until crystallization begins, and then gradually mole) of crude disodium tetrahydroxy-p-benzo diluted with 20 ml of acetone. The crystals are quinone (see section 3.2) and 55 g of active manganese collected on a filter, washed successively with 10 ml dioxide. After 5 min, the mixture is heated to of cold 1: 1 acetone-water mixture and 20 ml of boiling, refluxed for 45 min, and filtered, and the cold acetone, and air-dried; wt, 2.1 g. By con manganese dioxide is washed with 800 ml of hot centration of the mother liquor, additional material water. The combined filtrate and washings are (0.6 g) is obtained. The octahydrate consists of treated with about 210 ml of concentrated hydro colorless, lustrous plates or prisms, mp 99 to 100 °C chloric acid in portions, giving a bright-yellow (decomposition). Infrared and ultraviolet absorp solution. To this is added a hot solution of 50 g tion spectra are recorded on pages 159 and 16l. of barium chloride dihydrate in 150 ml of water, A characteristic color test [26] for IV involves with stirring; the mixture is heated to 85 to 90 °C, heating the compound with a saturated. aqueous cooled, and kept at room temperature. The re solution of barium chloride; bright-red barium sulting, lustrous, yellow plates of barium croconate rhodizonate is precipitated, following disproportion a monohydrate are collected on a filter, washed tion [8, 221. successively with watcr and cthanol, and air-dried; wt, 22 to 23 g. 6. eroconic Acid (V) [28] 6.4. Conversion of Barium Croconate to Sodium ) Crocona te '- 6 .1. Discussion Barium croconate (17.5 g; 0.06 mole) is added in Orocon1c acid (V) is one of the first enediol ic acids small portions, with stirring, to 150 ml of a 10- to have been reported. Since its discovery by percent aqueous solution of anhydrous sodium Gmelin [29] in 1825, it has engaged the attention of carbonate. The mixture is boiled for 5 min and many workers [10, 30- 39]. As pointed out by filtered; the barium carbonate is washed with 30 Hirata and coworkers [36], the fLnion has an unusual ml of hot water, and the combined yellow filtrate resonance structure. Oroconic acid is formed from and washings are diluted with 20 ml of glacial acetic a variety of polyhydroxybenzene denvatives by acid, heated to boiling, and cooled in ice. Disodium oxidation followed by a rearrangement of the benzylic croconate trihydrate separates in long, yellow acid type. It can be efficiently prepared by oxida crystals, which are collected on a filter, washed with tion of tetrahydroxy-p-benzoquinone or rhodizonic 40 ml of ice water, and air-dried; wt, about 10 g. acid witb manganese dioxide. In the process, the A second crop (2.5 to 3.5 g) is obtained by adding benzene ring is degraded, with elllnination of carbon about 200 ml of 95-pcrcent ethanol to the mother dioxide. The reaction was discovered by Nietzki liquor and cooling the solution. ,I [32] and has since been used by many workers. Dipotassium croconatc may be prepared similfLrly. .c:;' The procedure given here resembles one described by Yamada and Hirata [40], and differs from prior 6.5 . Croconic Acid Trihydrate methods in that it starts wiLh the crude mixture of sodium salts obtained from the condensation of Barium croconate (55 g) is added in small portions glyoxal (instead of with pure sod ium rhodizonate) to 200 ml of mechanically stirred, aqueous sulfuric - I and uses a special type [41] of active manganese acid (containing 20 ml of concentrated acid) at 55 I dioxide as the oxidant. to 60 °0; stirring is continued for 30 to 45 min. The .. barium sulfate is separated by filtration, washed with r 6.2. Preparation of Active Manganese Dioxide 25 ml of hot water, and discarded. The combined ,, : filtrate and washings are evaporated to dryness under : Commercial manganese carbonate (500 g) in a diminished pressure, the residue is dissolved in a hot flat-bottomed tray or dish is heated in an oven at solution of 25 ml of absolute ethanol and 150 ml of .) 295 to 310°C for 12 to 18 hr. After being cooled, dioxane, and the solution is treated with a small the product is treated with sufficient aqueous nitric quantity of decolorizing carbon and filtmed. The J acid (15 to 20 ml of concentrated acid per 100 ml of filtrate is concentrated under diminished pressure at I solution) to decompose any residual carbonate and 40 °0 until crystallization begins, and the mixture is , to give a strongly acid solution. After 30 to 45 dilu ted with benzene to incipient turbidity and cooled. 156
L_ After several hoUl's, the resul ting cry tftls are sepa 186 1. Particularly noteworthy inves tigations were ? rated by ftltration, washed with benzene, and dried made by Nietzki [32], Homolka [44], and Eistert and ~ in a vacuum desicclt tol'. By concentration of the coworkers [22 ]. The procedure given in the present mother liquor, additional crystflls are obtftined ; the paper is a modification of that of ietzki. com bined yield of croconic acid trihydrate is about 20 g. Infrared and ultraviolet absorption spectra are I recorded on pages 159 and 161. 7.2. Preparation of Leuconic Acid Pentahydrate I Anhydrous croconic acid is prepared by heating :> the trihydrate at 120 DC for 2 to ~ hI's; it slowly Purified anhydrous croconic acid (2 g) , or an decomposes above 150 DC. Crocolllc aCld may be equivalen t amount of the trihydrate, is ftdded in ~· characterized as the dimethyl ether, mp 11 3 DC [35]. portions, with stirring, to 20 ml of ice-cold, concen I Small quantities of croconic acid may be prepared trated nitric acid during 3 min, and the mixture is by passing a solution of 5 g of disodium croconate in stirred nntil evolution of nitrogen dioxide ceases l. 300 ml of water through 80 ml of a cation-exchange (about 10 min). Then 20 ml of ice-cold methanol resin (Amberlite 120- H+), concentrating the effluent is added, and the mixture is stirred while crystal ,;- under diminished pressure, and crystallizing the prod lization of leuconic acid pentahydrate occurs; after I uct from dioxane with the addition of ethel', benzene, 10 min, the cryst als are separated by filtration, (' or pentfine. washed with methanol, ftnd air-dried; wt, about 2.7 g. 6 .6 . Preparation of Manganese Croconate For recrystallization, the compound is dissolved Trihydrate in the minimal quan tity of water ; the solution is treated with decolol'izing carbon and fil tered, and A solution of 5 g of croconic acid trihydrate in the fil trate is concenLr ft ted under diminished pressure 50 ml of hot water is treated, with stirring, with a at 40 DC to about 5 m1. After the addition of '" bot, saturated, aqueous solution of manganous ace several drops of con ce ntmted nitric ~Lc id , the solu tate until a precipitate form s. Tbe mixture is cooled tion, on cooling, yields colorless crysLals of leuconic to room temperature, and the resulting greenish-yel acid pen tahydrate. Infrared and ultraviolet absorp low crystals are separated by ftltration. The product tion spectra are given on pages 159 and 161. is recrystallized from water by the addition of ace- Crystalline leu conic acid pen tahydrate may be > tone; the yield is almost qwmtitative. isolated from concentrated, aqueous solution by I Analysis: Calculated for C5:Mn0 5·3HzO : C, 24 .1 ; adding a 1: 1 mLxture of 2-propftnol ftlld ethanol; , H , 2.41. Found : C, 24 .0; H , 2.5. this product is devoid of nitric acid. The pen tahydratt' melts with dehydration at 11 5 6.7. Analysis of Croconic Acid to 11 8 DC, followed by slow decomposition at 158 to 162 DC. Lellconic ftcid mfty be chamcterized as The purity of samples of croconic acid may be the pen taoxime [32], mp 172 °C. In the prcsen t determined by titration with a standard solution of study, it has b een found that the oxime may con potassium permanganftt e (see eq (1)) . venien tly be recrystallized from N,N-climethylforma mide. r- 12 KMn04 + 23 H2S0 4 + 5 NazCsOs ~ 6 1\:2S0 4 + vVhen a sftturated solution of sodium carbonftte is :, added to an aqueous solution of leuconic acid, a j 12 MnS0 4+ 25 CO2 + 5 NaZS0 4 + 23 H 20 (1 ) pink color is produced, followed by deposition of a difficultly soluble, white precipitate of the sodium A 50-mg sample of disodiurn croconate, previously salt of mesoxalic ltcid [44]. dried at 120 DC for 1 hI', is transferred to a 250-ml Erlenmeyer flask with 25 to 50 ml of water. Sulfuric ? acid (50 ml of 3.6 N ) is added, and the solution is heated to 80 DC and rapidly titrated with O.I-N 8 . Spectrophotometric Measurements po tassium permftnganate to the complete disappear ance of the original yellow color. Then 5 ml of a Figure 1 reports infrared spectrograms for the 5- percen t solution of zinc chloride is added, and the freshly prepared, crystalline compounds in Nujol addition of permanganate is continued drop wise wi th mulls. The measurements were mftde with a swirling, until a faint pink color, stable for about 1 P erkin-Elmer Infracord Model 137 (double beam)
:'- min, is produced. A 50-mg sample of disodium spectrophotometer equipped with a prism of sodium 1 croconate monohydrate consumed 29.20 ml of chloride for the 2- to 15-J..L range. O.I-N potassium permanganate; calculated for rrhe ultraviolet absorption measurements given JazC50 s· HzO : 29.40 m1. in figure 2 were made with a Beckmftll DK- 2 spec trophotometer with matched, l-cm quar tz cells 7 . Leuconic Acid (Cyclopentanepentone, VI) and the appropriate solvent as the reference standard. In the course of time, the spectra for some of the [42] compounds change, pres umably from oxidation 7 .1. Discussion reactions. To minimize oxidation, freshly boiled solvents were used, b u t complete exclusion of oxygen > Leuconic acid was first prepared by Will [43] m was not attempted. 157 ------
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.. : F](TRE 1. I nfrared spectrograms oj matel"ials in N ujol mulls. / \ 1, Hexahyclroxybenzene; II, tetrah yc1roxYQuinon e; III, rhoc1izonic acid dillyt1rate. 158 em-I :J 4 000 3000 2000 1500 1200 1000 9 00 800 700
100
8 0
;t.
~ 60 z « " f- f- i I, 20 0 ( 4 5 6 7 8 9 10 II 12 13 14 IS WA VELENGTH .fL ! em-I 4 000 3000 2000 1500 1200 1000 900 800 700 100 8 0 ~ tJ 6 0 z ;0- ~ ~ ::; ;, ~ 4 0 I « a: f- 20 0 4 5 6 7 8 9 10 I I 12 13 14 IS L WA VE LENGTH. fL I ? em-I 4000 3000 2000 1500 1200 10 00 900 8 00 700 100 -'\ 80 ~ ~ 60 z « f- 'C f- 1 :;;; ~ 40 « a: • f- ~ . 20 0 4 5 6 7 9 10 I I 12 13 14 IS WAVE LENGTH. fL ..; FIGU RE 1. I nfra/'ed spectrograms of materials in Nujol mulls- Co ntinued '> 1\"' , 'rriquinoyl octahydrate; Y, croconic acid trih ydratc; ' ·1, leuco nic acid pentuhydrate. 670682- 6:1--6 159 .3 c w u Z 260 270 280 290 300 320 340 WAV ELENGTH. m f1- 4 r----,-----r----r---,---.---,---r-~--~~-~--r_~._,_._--r__r--,_,1'", \ .3 \ B w u z \ \ ~1 ~'" .2 o ----- \ (f) ...... \ en -- ...... , '" ...... IT .5 r-----~----._--_,----,----r--_,---.--_r--,__,--.__r-,--r_,_._--r_-r~'~--, B / \ I \ / \ / A \ / w I ~ .3 ----- /, - ...... CD -- '"0: --- ...... o ...... ~.2 "- O L-__~ ___L __ ~ __-L __ ~~ __~-L~ __~~~~~~~~~~~ 220 230 240 250 260 270 320 340 WAVELENGTH. m f1- FIGURE 2. Ultraviolet spectrograms of materials. 1. H exa hydroxybenzene. Curve A, 7.39 mg of I in 100 ml of 6N HCl in methanol, 3 min after dissolution; Am" at 278 m~. Curve B, 67 mg of the hexaaeetate of I in 200 ml of glacial acetic aCid, 10 min after dissolution; Am" at 263 m~ . II. T etrahydroxYQuillone. Curve A, 3.82 mg of II in 1000 ml of 2N aqueo us HCl, 24 hr after dissolution; Am" at 308 ". m~. Curve n, 7 mg of II in 1000 ml of m ethanol, 30 min after dissolution; Am" at 312 m~. III. Rhodizonic acid dihydrate. Curve A, 6.87 m g of III in 1000 ml of 2N aqueous H CI 24 Ill" after dissolution; Am., at 235 m~ a nd at 319 m". Curve n, 8.58 mg of III in 1000 ml of m ethanol, 5 min after dissolution; Am", at 235 m" and at 323 m~ . In the visible region, III sho,," s absorption at 443 m~ and at 487 m~ (sh) . 160 I~-- J l .7 I .6 .5 w , U Z r' « m 4 0:: 0 >- Cf) m « .3 r .2 ,l_ ll[ ). 0 220 230 340 .8 .7 .6 w u .5 z « m 0:: 0 .4 Cf) m « .3 .2 .1 "Sl. 0 220 230 240 250 260 270 280 290 300 320 340 WAVELENGTH, m f-L I ~ w ~ . 2 « (Jl o0:: Vl lZI «(Jl o ~~~~~~~~ __~~~ 270 280 290 300 320 340 WAVELENGTH, m f-L F IGU RE 2. Ultraviolet spectrograms oj materials- Continued. IV. 'J'riquinoyl octahydrate. 3.24 mg of I V in 100 ml of 2N aqueo us NaCI 1.5 1lr after dissol ution; },mu at 267 m". In the visible region , I V shows marked a bsorpLi on at 363 m", 440 m" (s h) and 480 m". V. Croconic acid tri hydrate. 5.87 mg of V in JOO ml of 2N aqueous J I CI, 10 min after dissolution; Am" at 23l m" and at 298 m". \ ' r. Lcuco ni c acid pentah ydrAte. 1.56.45 mg of VI in 50 m1 of ,," atcr, 5 min after dissol ution; },m" at 328 m". 161 9. References [22J B. Eistert, G. Buck, E. Kosc h, and F. Spalink, C hem. Del'. 93, 1451 (1960). [2:3J Bcil steill s Handb. Org. Chemi c 7, 907, Springer, Berli n [I ] T. l'o ~ tel"llak, Helv. Chim. Acta 19, ]:)33 (1936); 240, (1925) . 1045 (1941). [2'1] .r. Lerch. Ann. 1240, 34 (1862) . [2] T. Posternak and J. Deshusses, Hel\'. Chim. Acta 4040, [25J R. ~ietzk i and F. K(~hrm a n, Bel'. 20, :322 ( l887). 2089 (1961). [261 F. H e nl(~, Ann. 350, 330 (1906) . [3] N. Z. Stall acev and M. K ates, J . Org. C hern. 26, 9J 2 [27] F. Berge1, Ber. 62, 490 (1929) . (1961) . [28] Beilstein s Hanelb. Org. Chemie 8, 489, Springer, Berlin [4] H. S. I sbell, Ann. Rev. Biochem. 12, 213 ( l94~ ). ( H125) . J [5 ] H. S. I sbell , J. Research NBS 32, 45 ( 1944). [29J L. Gmelin. Anll. Phys. 40, :n (1825). [6] n. W~ e s t a lld Hsien-Ying Xiu, J. Am. Chcm. Soc. 840, [30) J . Li ebig, Ann . 11, 182 (1834) . 1324 (1962) ; Chcm. Eng. News 400,40 (1962). [31) R Nietzki alld T. Bcnekise r, Bel'. 19, 293 (1886). " [7] Beilsteins Handb. Org. Chemic 6, 1198, Springer, Berlin [:)2) n. Kietzki, Ber. 20, 1617 (1887). "'I (1923) . [3:3) R l'\ietzki, Ber. 2:1,3136 (1890). [8] R. Nietzki alld T. Bellckiser, Bel'. 18, 1833 (1885). [34] O. Gelormini and E . Artz, J. Arn. Chem. Soc. 52, 2-+83 [9] A . .T. Fatiadi (with W. F. Sager), -:\1[. S. Thesis, 1959, (1930). The George Washington University, Washington , D.C. [35\ n. Malachowski and S. Prebcnc1owski, Ber . 71, 2241 [10] R. K ietzki and T. Benckiser, Ber. 18, 499 (1885) . (1938) . [11] P. VV. Preisler and L . Berger, J. Am. Chem. Soc. 64, (j7 [36] Y. Hirata, K. Inukai, ancl T. T ~ ujiuchi , J. Chem. Soc. (1942) . Japan 69, 63 ( l948) ; C. A. 407, 5902 (1953) . [12] R. C. AndCl'son and E. S. Wallis, J. Am. Chem. Soc. 70, . [37) F. Arcamonc, C. Prevost, and P. Souchay, Bull. Soc . 2f131 (1948). Chim. Francc 1953, 891. [13J A. J. Fat iadi and W. F. Sager, Org. Syntheses 402, (a) 66, [;)8J S. Ruthkowski, Rocz. Chem . 36,169 (1962) . (b)90 (1962). [39) B. Carlqu ist and D. Dyrssen, Acta Chem. Srand. 16, [ 14] LOLli ~ F . Fieser and M ary Fieser, Ad"anced Orga nic 94 (1962). Chelilistry, r. 757 (Rcinllold Publ. Corp., K cw York, [40] Ie Yamada and Y. Hirata, Bull . Chem. Soc. Ja pan 31, N . Y ., 19(H). 550 (1958) . [15J B. Homolka, Bel'. 54-, 1393 (J 921). [41) iVI. Harfenist, A. Barley, and W. A. Lazier, .J. Org. [161 R. Robil~ S OIl and C. Vasey, J. C hem. Soc. 1941, 660. Chem. 19, 1608 (1954). [17J Bpilstein s Handb. Org. Chemi c 8, 5:34, Springer, Berlin [42] Beilsteins Handb. Org. Chemic 7, 905, E:priu ger, Berlin ( 1925 j • (1925). [18] H. J. Backer and S.v.cI. Baall, Rec. Trav. Chim. 56, [431 H. Will, Ann. 118, 177 (1861) . 1161 (1937) . [44] B. Homolka, Ber. 55, 1310 (1922). [19J R. Kuhn, G. Quadbeck, and E. Rohm, Ann. 565, I (1949) . [20J B. Eistert alld G. Bock, Angew. Chem. 70, 595 (1958). [21] Beilsteins Handb. Org. Chemi e 8, 535, Sprin ger, Berlin (1925). (Papor 67 A2- 202 ) /' I., j I I ':'1 .. I 'f • J 162 ~-