glycine and acetylglycine. H. D. D a k in (J. Biol.
Chem., 1929, 82, 439—416).—The reaction between glycine and an aromatic aldehyde in presence of acetic anhydride is complicated by the tendency to the formation of the iV-a.rylidene derivative of glycine (for which an alternative ring structure is proposed).
I t is accordingly found th a t improved yields of the azlactones of a-acetamidocinnamic acid and homo- logues are obtained using acetylglycine. Benzylidene- glycinc, from glycine with a large excess of benzalde- hyde in presence of acetic anhydride, has m. p. 207°
after darkening a t 180°. Glycine is conveniently acetylated by warming in suspension in acetic acid with the theoretical amount of acetic anhydride.
Acetylglycine was condensed with benzaldehyde to give the azlactone of a-acetamidocinnamic a c id ; with salicylaldehyde to give th e azlactone of o-acetoxy- a-acetamidocinnamic acid, m. p. 203—205°, yielding on treatm ent with alkali and acidification <x.-acetamido- coumarin, m. p. 203—204°; with ^-hydroxybenz- aldehyde, yielding the azlactone and acid obtained by Bergmann and Stern (A., 1926, 743); with piperonal to give the azlactone of a.-acetamido- piperonylic acid, m. p. 183—184° (acid, m. p. 220—
221°); with jo-nitrobenzaldehyde to give the azlactone of a-acetamido-'p-nitrocinnamic acid, m. p. 185—186°
(acid, m. p. 234—235°). C. R. Ha r in gt o n.
Isom erism am ong 9-substituted fluorenes ? A. Kl ie g l [with E. Th o m a e] (Ber., 1929, 6 2 , [22], 1327— 1335).—Fluorenone is reduced by zinc dust and boiling acetic acid to a m ixture of fluorenyl alcohol, m. p. 156°, and fluorenopinacol, m. p. 190—
192° (cf. Gomberg and Bachmann, A., 1927, 245), w ith small amounts of 9-acetoxyfluorene, difluorenyl ether, and diphenylenephenanthrone; indications of the formation of an isomeric form of fluorenyl alcohol are not obtained. 9-Methoxyfluorene, m. p. 43-5°, is prepared by the action of boiling m ethyl alcohol and powdered silver nitrate on 9-chlorofluorene.
A ttem pts to repeat th e preparation of p-fluorene- 9-carboxylic acid, m. p. 232°, according to the directions of Schlenk and Bergmann (A., 1928, 1034) resulted in the formation of an acid, m. p. 221—223°
(slight decomp.), identical in m. p. with the ordinary a-acid b ut differing therefrom by crystallising in needles. The technical acid also separates in needles from benzene; this was the sole form in which the acid could be isolated from sodiofluorene prepared by a variety of methods. Similarly, endeavours to isolate Schlenk’s (3-9-methoxyfluorene-9-carboxylic acid, m. p. 172—173°, gave only the known acid, decomp. 184°, according to the rate of heating.
Schlenk’s “ isomeric ” benzhydrylfluorene, m. p. 187°, is recognised as a m ixture of benzhydrylfluorene, m. p. 217°, with 5-tetraphenylethane and little di
fluorenyl, m. p. 240°. The action of 9 : 9-dichloro- fluorene on disodiobenzophenone yields, according to Schlenk and Bergmann, diphenyldiphenylene-ethylene oxide and two isomeric diphenyldiphenylene-ethyl- enes, m. p. 225° and 213°, respectively; the “ isomer- ide ” of m. p. 213° is considered to be an isomorphous m ixture of the compound, m. p. 225°, and diphenyl
diphenylene-ethylene oxide for the following reasons.
The m. p. is depressed slightly by addition of an approximately equal q u antity of the “ ethylene,”
m. p. 225°, and raised by similar addition of the oxide. Fractional crystallisation from benzene per
m its the isolation of the “ ethylene,” in. p. 225°, or the oxide, according to the relative am ount present in the original mixture. If approximately equal quantities of “ ethylene,” m. p. 225°, and oxide are mixed in hot light petroleum, b. p. 120—180°, and the solution is cooled, the product separates in a form indistinguishable from the “ isomeride ” except in being colourless. Treatm ent of the “ isomeride ” with acetyl cldoride places beyond doubt the presence in it of the oxide which when homogeneous is con
verted by the reagent exclusively into benzoylphenyl- fluorene; from the “ isom eride” a m ixture of the last-named compound and the “ ethylene,” m. p.
225°, is produced. There appears, therefore, no present reason for abandoning the tried hypothesis of the uniplanar arrangement of the rings in fluorene.
H. Wr e n.
H exaliydrophthalic acids. G. Va v o n and P . Pe ig n ie r (Bull. Soc. chim., 1929, [iv], 4 5 , 293—
299).—Hydrogenation of phthalic acid or of methyl phthalate in acetic acid in presence of platinum - black affords the cts-hexahydro-derivative, hydro
genation of the free acid being very slow. The 1 -quinine Balt of ci's-methyl hexahydrophthalate, m. p.
141-5— 142°, [a]D -136-5°, with alcoholic sodium
hydroxide yields l-cis-melhyl hydrogen hexahydro
phthalate, m. p. 48—49°, [a]D —6-67°, which on cold hydrolysis loses its activity and yields inactive cis- acid, m. p. 190° (decomp.). Similarly, the cis-hcxa- hydrophthalamide, obtained in 85% yield from the anhydride, on resolution with quinine affords the l-cis-hexahydrophthaiamide, m. p. 165° (decomp.), [a]D —15-4° [quinine salt, m. p. 149—150° (decomp.), [a]D — 12S°], which, like the racemic amide, when heated a t 190—200° for 1 hr., gives the inactive imide, m. p. 134-5— 135°. These results support the Bayer formula and not th a t of Sachse (A., 1890, 1386) if the formulae are regarded as rigid. Since, however, the ira?w-acid affords an anhydride, m. p.
140°, differing from the «s-anhydride, in. p. 32°, and existing a t least partly in the simple form C6H 10< c o > O (mol. wt. in camphor 218), a resultCO more readily interpreted by the Sachse formula, the authors regard cycZohexane as possessing a mobile non-planar structure, pure substances consisting of mixtures of molecules with different configurations, the mobility of which can be diminished or suppressed by the two substituent radicals (cf. Mohr, A., 1919, ii, 229; Boeseken, A., 1921, i, 843).
R. Brightman.
ci's-irajis-Isom erism and steric hindrance.
VIII. M ethyl hydrogen hexahydrophthalates.
G. Va v o n and P . Pe ig n ie r (Bull. Soc. chim., 1929, [iv], 4 5 , 299—302).—A t 39° cis-hexahydrophthalic acid is esterified with m ethyl alcohol in presence of hydrogen chloride about 1-4 times more slowly than the ira?w-isomeride, m. p. 213—218° (decomp.) (anhydride, m. p. 142°). Similarly, the tram-metbjl hydrogen hexahydrophthalate, m. p. 95—96°, is hydrolysed by sodium or potassium hydroxide in 75% alcohol a t 39°, five times, and by aqueous sodium hydroxide a t 39° and a t 0° six times and ten times, as rapidly as the c?s-isomeride.
R. Brightmas. Conjugated com pounds. VII. Additive form ation of cyclohexenes. E. H. Farmer and F. L. Warren (J.C.S., 1929, 897—909).-The possibility of modifying the cj/cZohexene ring-forming tendencies of butadienoid hydrocarbons has been studied using maleic anhydride as an addendum.
The formula, § h —CH^—CH—C O ^ 0 , given by 'D!elS and Alder (A., 1928, 1018) to th e condensation
product from butadiene and maleic anhydride is correct, since pp'-dicarboxyadipic acid is obtained from it by the action of dilute aqueous potassium permanganate. Maleic anhydride and (3y-dimethyi-
butadiene yield directly 4 : 5-dimelh)/l-cis-A‘,-tetra- hydrophtlialic anhydride, m. p. 78°, which, by heating with water, gives 4 : S-diinethyl-cis-^-tetraJiydro-phthalic acid, m. p. 180—192°. Ozonolysis of a chloroform solution of the anhydride l e a d s to the ketonic acid [C0Me-CH2-CH(C02H)-]2 (or its cychscd equivalent, S-acetylA-methylcyclopentan-i-ol-l ■
carboxylic acid), m. p. 186°. ,
o£-Dibromo-Aw-hexadiene, when heated witl maleic anhydride in benzene solution, forms 3 : o-at- bromomethyl-cis-A^tetrahydrophthalic anhydride, in. P- 98°. This compound, by boiling with aqueous
OEGANIC CHEMISTRY. 813
sodium carbonate, is converted into the dilactone, m. p. 159—163° after previous softening a t 147°, of 3 : 6-dihydroxymethyl-cis-A4-tetrahydrophthalic acid.
The dilactone, by catalytic reduction, gives the lactone, m. p. 119— 120°, of 3 : 6-diliydroxymethyl- hexahydrophthalic acid. Attem pts to oxidise the last-named acid to hexahydroprehnitic acid failed, only oxalic acid being definitely isolated.
It is concluded th a t cycloliexene formation from open-chain butadienes is complete and remains un affected (exccpt as regards velocity) by variation of positions of alkyl substituents.
Maleic anhydride and ethyl trans-trans-muconate combine when heated to give 3 : 6-dicarbethoxy-A3- teirahydroplithalic anhydride, m. p. 185—188°, con
verted by alcoholic hydrogen chloride into the corre
sponding tetraethyl ester, m. p. 75°; the last-named compound, by alternate addition of bromine and removal of hydrogen bromide with diethylamine or pyridine, gives, after two such series of operations, an acid, C10H 8O8 (dihydroprehnitic acid ?), m. p. 241°
(decomp.). The above dicarbethoxy-A3-tetrahydxo- phthalic anhydride gives oxalic acid extensively on treatment with permanganate or ozone. The corre
sponding acid is reduced by hydrogen and colloidal palladium to 3 : 6-dicarboxyhexahydrophthalic acid (hemhydroprehnitic acid) (monoliydrate, m. p. 168°, tetraethyl ester, b. p. 238°/15 mm., dianhydride, m. p.
223—225°). E thyl cis-cis-muconate does not react with maleic anhydride.
Sorbic acid and maleic anhydride in benzene solution at 100° yield 6-carboxy-3-methyl-cis-A5-tetra- bjdrophthalic anhydride, m. p. 174°; boiling with water gives the corresponding acid, m. p. 194°, with anhydride formation, catalytic hydrogenation (pallad
ium) of which gives Q-carboxy-3-methyl-eis-hexahydro- phthalic acid (monohydrate, m. p. 194—196°).
Permanganate oxidation of cycZopcntadiene- and cj/cfohexadiene-maleic anhydride condensation pro
ducts gives in the first case a tetrabasic acid (either cydopentane-1 : 2 : 3 : 4-tetracarboxylic acid or cyclo- butane-1 : 2 : 3-tricarboxy-4-acetic acid), m. p. 181—
182° (with anhydride formation) (tetraethyl ester, b. p.
226°/14 mm.), and in th e second case, 3 : 6-dicarboxy- hexahydrophthalic acid, m. p. 168° (above).
Addition of maleic anhydride to irans-hexatriene occurs in benzene solution a t the ordinary tem perature, giving S-ethylidene-cis-Ai -tetrahydrophthalic anhydride, m. p. 5T5°, b. p. 148°/6 mm. (anilic acid, p. 174°); th e corresponding acid, obtained by boiling with water, has m. p. 164—166° (with anhydride formation). Ozonolysis of the above
^hydride yields acetaldehyde and a strongly enolic aldehyde; oxidation of the above acid by per
manganate yields finally only oxalic acid.
«s-Hexatricnc and maleic acid combine to give an impure liquid anhydride, b. p. 120—150°, which yields an anilic acid and an ethylidene-cis-tetrahydro- phthalic acid identical with those of the inms-series.
«iter many distillations the same ethylidene-cia- tetrahydrophthalic anhydride was isolated in a crystalline condition. R. J . W. Le Fevre.
Synthesis of an isom eride of thyroxine, and o£ related com pounds. C. R. H a b i n g t o n and
W. McCa r t n e y (J.C .S ., 1929, 892—897).—Di-(4-methoxyphenyl)methyl chloride (A., 1922, i, 148) condenses with ethyl potassiophthalimidomalonate in xylene a t 145° to give a 75% yield of ethyl di-(4- methoxyphenyl)methylphthalimidomalonate, m. p. 106°, which by hydrolysis with potassium hydroxide and decarboxylation a t 180—200°/13 mm. affords the anhydride of a.-o-carboxybenzamido-$$-di-(‘i-methoxy- phenyl)propionic acid, m. p. 209—210°, hydrolysed by hydriodic acid (d 1*7) and acetic anhydride to a-amino-
$$-di-(4=-hydroxyphenyl)propionic acid (I), m. p. 241°
(decomp.) after softening a t 190—200°; by treatm ent with iodine and ammonia I is converted into pp-di- (3 : 5-di-iodo-4:-hydroxyphenyl)-a.-aminopropionic acid, m. p. 218°. Decarboxylation of I a t 290—315°/2 mm.
in portions of 0-5 g. furnishes fifi-di-(4.-hydroxyphenyl)- ethylamine, m. p. 207—208° (hydrochloride, m. p. 275°;
tribenzoyl derivative, m. p. 200°), which by treatm ent with iodine and ammonia affords pj3-cZi-(3 : 5-di-iodo- 4:-hydroxyphenyl)ethylamine (II), m. p. 232— 233°
(decomp, with liberation of iodine). Similarly, di- phenylmethyl bromide (cf. A., 1925, i, 656) with ethyl potassiophthalimidomalonate gives ethyl diphenyl- methrylphthalimidomalonate, m. p. 117° (yield 57%), hydrolysed, decarboxylated, and dehydrated to the anhydride of a-o-carboxybenzamido-fip-diplwnylpro- pionic acid, m. p. 214—215°; the latter by hydrolysis with hydriodic acid (d 1-7) and acetic anhydride affords a-amino-$$-diphenylpropionic acid, m. p. 236° (de
comp.). Bromination of 3 : 5-di-iodothyronine in glacial acetic acid gives a 45% yield of 3 ': 5'-dibromo-3 : 5-di-iodothyronine, m. p. 244-5°.
Although I is isomeric with and retains the character
istic o-di-iodophenolic group of thyroxine, it exhibits no trace of any type of physiological a c tiv ity ; I I is similarly inactive. An improved preparation of PP-diphenylethylamine, m. p. 39—40°, b. p. 180°/
15 mm. (hydrochloride, m. p. 259°; picrate, m. p.
216—217°), is described. C. W. Shoffee. A lkyl- and aralkyl-resorcinolcarboxylic acids.
H. Stenzl.—See B., 1929, 427.
Substances related to cochinillic and carm inic acids. II. Synthesis of a-coccinic acid (m-oxy- uvitic acid). A. N. Meldrum and R. L. Alim-
ohandani (J. Indian Chem. Soc., 1929,6,253—258).—
Condensation of 3 -inethoxy-p-toluic acid with chloral hydrate in presence of sulphuric acid affords, in ad
dition to 3-methoxy-6-ppp-trichloro-a-hydroxyethyl- p-toluie acid (I) (A., 1925, i, 1272), small amounts of 3-meihoxy-6-a.p|3fi-telrachloroethyl-^-toluic acid (II), m. p. 200—201°, and the 2-swip/&o-derivative (barium salt) of I. W hen I is heated with sulphuric acid for a short tim e or treated with hydrogen chloride in presence of sulphuric acid a t the ordinary tem per
ature, I I results. Reduction of I I with zinc dust and acetic acid gives 3-methoxy-6-pp-dichloroethyl-'p- toluic acid, converted by treatm ent with sulphuric acid a t 70—80° into 2-methoxy-4:-methyl-5-carboxy- methylbenzoic acid, m. p. 164— 165° (barium salt +1-5H ?0). Treatm ent of I I with hot 20% potassium hydroxide solution affords a^o^-lrichloro-^-metJwxy- Q-methylstyrene-2-carbo-xylic acid, m. p. 185—187°.
Hydrolysis of I with barium hydroxide solution yields 4:-methoxy-5-carboxy-2-methylmandelic acid, + H 20 ,
m. p. 105—110° with effervescence after sintering a t 95—100°, m. p. (anhydrous) 162—163° (barium salt + 4 H 20), oxidised by potassium perm anganate to
‘i-meihoxy-5-carboxij-o-ioluoylformic acid, m. p. 211—
212° (barium salt + 2 H 20), and converted by treatm ent with sulphuric acid a t 80—100° into 3-methoxy- Q-aldehydo-'p-toluic acid, m. p. 176—177°. Oxidation of this with potassium permanganate affords 4,-meth- oxy-G-methylisophtiialic acid, m. p. 250—252°, ob
tained also by similar oxidation of I. Demethylation of this methoxy-derivative with 10% hydriodic acid yields 4-hydroxy-6-methyU'sophthalic acid [a-coccinic acid], m. p. 320—322° [(decomp.); (lit. 298° and 310°);
barium salt + 2 H 20 , loses 0-5H20 a t 110—125°;
calcium salt + 4 H 20 , loses 2-5H20 a t 110—115°].
The a-coccinic acid (m-oxyuvitic acid) of Oppenheim and Pfaff (A., 1874, 1161) is impure. H. Bu r t o n.
[Attempted] syntheses of (i-opianic acid. I.
S. N. C h a k r a v a r t i (J. Indian Chem. Soc., 1929, 6, 207—229).—Various unsuccessful synthetic schemes are described. Reduction of 6-nitro-2 : 3-dimeth- oxybenzaldehyde (I), m. p. 110°, obtained together with the 5-nitro-isomeride by nitration of o-veratralde- hyde (cf. Perkin, Robinson, and Stoyle, A., 1925, i, 39), with ferrous sulphate and ammonia gives 6-amino-2 : 3-dimethoxybenzaldehyde (hydrochloride; benzoyl derivative, m. p. 150°; plienylhydrazone, m . p. 133°), which readily eliminates water from 2 mols., forming an azomeihine, m. p. 235°. A ttem pts to introduce a cyano-grouj) in place of the amino-group failed.
A ttem pts to oxidise ^-meconine with various oxidising agents were either negative or resulted in complete de
gradation (cf.Salomon, A., 1887,585; Edwards,Perkin, and Stoyle, A., 1925, i, 404). Bromination of fm e c - onine a t 150° in bright sunlight yields a small amount of a substance, m. p. above 280°,"together with an acid (probably 6-bromo-2-aldehydo-3:4-dimethoxybenzoic acid), m. p. about 200°, and a compound, m. p. about 90°. Methyl 4'¡-meconinate, m. p. 72—73° (from the silver salt and m ethyl iodide), is converted by tre a t
m ent w ith thionyl chloride in pyridine, phosphorus pentachloride in chloroform, hydrogen chloride in presence of ether and anhydrous sodium sulphate, or hydrobromic and acetic acids, into .¿-meconine. The last-named substance is unaffected by phosphorus pentachloride a t 160°, or hydrobromic and acetic abids.
2-Aminoveratric acid is converted by the usual method into 2-cyanoveratric acid, (II), m. p. 208—209°, which is readily hydrolysed by dilute hydrochloric acid to hemipinic acid. A ttem pted conversion of I I into 2-aldehydoveratric acid by Stephen’s m ethod (A., 1925, i, 1131) resulted in the formation of hemi- pinimide.
W hen 2 : 3-dimethoxycinnamic acid (improved m ethod of preparation given) is treated with an excess of nitric acid (d 1-5) below 0°, a dinitro-2 : 3-dimethoxy
cinnamic acid, m. p. 198°, is formed. W ith nitric acid (d 1-42) a t 10—20°, about 10% of 6-nitro-2 : 3-di- methoxycinnamie acid (III), m. p. 220° (methyl ester, m. p. 150°; ethyl ester, m. p. 90°), is obtained together with the 5-nitro-isomeride, m. p. 231° (methyl ester, m. p. 154—155°), separable through the solubility of the methyl esters in alcohol. Condensation of I with malonic acid in presence of pyridine and piperidine
affords I I I , oxidised by potassium permanganate in presence of aqueous sodium carbonate and benzene to I. Reduction of I I I with ferrous sulphate and ammonia gives G-amino-2 : 3-dimethoxycinnamic acid, m. p. 179°, converted by th e usual method into
6-cyano-2 : 3-dimethoxycinnamic acid, (IV), m. p. 238°.
Hydrolysis of this with 10% sodium hydroxide solution yields Q-carboxy-2 : 3-dimethoxycinnamic acid (V), m. p. 194°. Oxidation of IV with potassium per
m anganate affords indefinite products, whilst V furnishes a substance, m. p. 202°. H. Burton.
T au tom erism oî o-nitro-com pounds. F.
A r n d t (Ber., 1929, 62, [.B], 1167— 1171 ; cf. A., 1928, 752, 759).—A reply to Tanasescü (A., 1928,177,178).
H. Wren.
“ O xidising " action of alkalis. II. Aromatic hydroxyaldehydes. G. Lo c k (Ber., 1929, 62, [5], 1177—1188; cf. this vol., 67).^—Hydroxyaldehydes which contain a free hydroxyl group in the ortho- or jpara-position to the aldehydo-group are not affected by solutions of potassium hydroxide, but react with the powdered alkali a t about 110° with formation of molecular quantities of hydroxy-acid and hydrogen.
This is true also of dihydroxybenzaldehydes which contain a hydroxyl group in the meta- as well as in the
^>ara-position ; for example, protoeatechualdehyde and its 3-methyl ether. Hydroxyaldehydes con
taining a hydroxyl group in the meto-position undergo the Cannizzaro reaction with cold potassium hydroxide solutions, whereas a t a higher tem perature thé alkali reacts with the hydroxybenzyl alcohol thus produced, giving hydrogen and hydroxy-acid, so th a t the final products of the two types of c h a n g e are ultimately identical quantitatively. The reaction may be ex
pressed by the scheme CgH^OKJ-CHO-fKOH^
C6H 4(0K ),C02K-f-H2, b u t the possibility of the intermediate formation of potassium hydride is not excluded. The following new d ata are recorded : Q-bromo-3-hydroxybenzyl alcohol, m. p. 142°; 6-ntfro-3-hydroxybenzyl alcohol, m. p. 120-5° rafter softening (potassium and lead salts) ; i-nitro-3-hydroxybem\ji alcohol, m. p. 97°; isovanillyl alcohol, m. p. 132°.
H. Wre n.
A ction of diazom ethane on piperonal. H.
E. Mo s e t t ig (Ber., 1929, 62, [5], 1271—1278; cf.
A., 1928, 887).—Safrole oxide, b. p. 140—145°/9 mm., is little affected by distillation under ordinary pressure or by prolonged agitation with concentrated sodium hydrogen sulphite solution, bu t is isomerised when boiled with pumice fragments soaked in 50% sulphuric
acid to 3 : 4-methylenedioxyphenylpropaldehyde (semicarbazone, m. p. 192—193-5° when slowly heated). I t is converted by cautious treatment with hydrogen chloride in light petroleum in t o the corre
sponding chlorohydrin, CjoH^OgCl, m. p. 47—48-5 after softening a t 46°. The oxide is tra n sfo rm ed by aqueous piperidine into p(or a)-piperidino-y-3' : 4- methylenedioxyphenylpropan-a.(oT (3)-ol, m. p. 42 44
(hydrochloride, m. p. 165—167° after softening at 163— 165°; chloroplatinate). S i m i l a r l y , with aqueous dimethylamine the oxide affords (3-(or ct)-dimetnyi- amino-y-3’ : i'-methylenedioxyphenylpropan-a.(ov P)-oi (picrate, m. p. 164— 165° after softening a t 163° ; very hygroscopic hydrochloride).
ORGANIC CHEMISTRY. 815
Finely-divided piperonal is added to an ethereal methyl-alcoholic solution of diazomethane at —15°.
The products formed are piperonylacetone, aceto- piperone, and safrole oxide (identified as the corre
sponding chlorohydrin and as the additive products with piperidine and dimethylamine). The same compounds result when an ethereal methyl-alcoholic solution of diazomethane is poured into an ethereal solution of piperonal. Acetopiperone when subjected to the same conditions as piperonal does not appear to react with diazomethane. Piperonylacetone reacts slowly, very probably with production of an oxide.
H. Wr e n.
Synthesis of safrovanillin from i.sosafro- eugenol. K . K a f u k t j and N. I s i i i k a w a (Bull.
Ind. Dep. Centr. Res. Lab. Formosa, 1928, 24, 24—
27).—Oxidation of zsosafroeugcnol with ozonised oxygen affords (60—80% yield) S-hydroxyA-ethoxy- benzaldehyde, m. p. 125° (oxime, m. p. 181—183°;
smicarbazone, m. p. 202—203°).
Ch em ic a l Ab st r a c t s.
Intermolecular condensation of styryl ketones.
III. Further exam ples of the ready form ation of bis-(styryl ketones). I. M. H e i l b r o n and F.
Irving (J.C.S., 1929, 931—936).—The interaction of benzaldehyde and m ethyl n-alkyl ketones gives both the simple styryl ketone and its dimeride. The solvent appears to be one of the main factors determining the formation of the mono- or bis-form; in aqueous alcohol the styryl ketone is formed, probably owing to its ready separation and consequent removal from the action of the alk ali; in absolute alcohol the dimeride is produced even at the same alkali concentration. The dimerides are more readily produced from the higher members of the series, and less easily with substituted benzaldehydes. Dimerides are formed from branched- chain ketones only when a t least one methylene group separates the radical from the carbonyl group. The styryl ketones differ widely from their bis-forms in m. p. and crystallise well; the bis-forms usually separate in masses of felted needles. By condensing the appropriate reactants with alkali under given conditions are obtained : bis(styryl n-propyl ketone), m. p. 194— 195° (cf. Vorländer, A., 1898, i, 27);
bis(stijryl n -butyl ketone), m. p. 175— 176°; bis(styryl mbutyl ketone), m. p. 202°, also prepared from styryl isobutyl ketone (cf. Gheorghiu and Arventiev, A., 1928,522); bis(4:-isopropylstyryl isobutyl ketone), m. p.
192—194°; bis(styryl n-hexyl ketone), m. p. 152°;
i-methoxystyryl n-hexyl ketone), m. p. 145—146°;
Mstyryl isoliexyl ketone), m. p. 177°; bis{styrijl- n-heplyl ketone), m. p. 144°; and bis(styryl n-octyl
«tone), m. p. 131—135°. Alkali condensation has also been employed to obtain the following styryl
«tones: styryl'n-hexyl ketone, m. p. 32—33° (cf.
“•» 1905, i, 214); 4:-methoxystyryl n-hexyl ketone, m. p.
styryl n-heptyl ketone, m. p. 52° (cf. A., 1905, i, -14); and styryl n-octyl ketone. I t is probable th a t the styryl y-methylamyl ketones (active and inactive) described by Rupe and Wild (A., 1917, i, 538) are dimerides. C. W. Sh o p p e e.
Natural sy stem for polym orphic form s of
P -methylchalkone [jp-tolyl styryl ketone].
Isomeric relationships in the chalkone series.
VII. C. W e y g a n d and H . B a t j m g a r t e l (Annalen, 1929, 469, 225—256; cf. A., 1926, 1041; this vol., 564).—-Instead of three modifications a, (3, and y, as previously recorded, jj-tolyl styryl ketone has been prepared in 13 crystalline forms, 7 of which are termed principal as distinct from subsidiary forms.
All three of the earlier modifications belong to the principal group. The following classification is made, the figures after the m. p. indicating the velocity of crystallisation from a fused mass a t 18—20° in 0-001 mm. per sec.: I, m. p. 74-5°; 89; II, m. p.
56-5°; 39; I I I , m. p. 55-5°; 30; (1 subsidiary form) ; IV, m. p. 54-5° ; 114; V, m. p. 45-5°; 19; VI, m. p.
48°; 4; (1 subsidiary form); VII, m. p. 44-5°; 20;
(4 subsidiary forms). Details , of preparation are given, together with the results of a study of the mechanism of transformation. R. A. Mo r t o n.
R elative stab ility of isom erides according to absorption spectra. V. Dehydration of glycols;
isom eric change of ethylene oxides. (Mme.) P.
R a m a r t- L u c a s and F. S a lm o n - L e g a g n e u r (Compt.
rend., 1929, 188, 1301—1303; cf. A., 1928, 760, 881, 1000 ; this vol., 441).—By dehydration of aa-di- phenyl-pfi-dimethyl- or ap-diphenyl-a'3-dimethyl- pinacols (I, II) or ethylene oxides (III, IV), only methyl aa-diphenylethyl ketone (V) or phenyl pheriyhsdpropyl ketone (VI) can be formed; from the glycols CRPh(OH)-CH2-OH (VII) (where R =
M e or CHaPh), only the aldehydes CHRPh-CHO (VIII) and the ketones CH2Ph-CO-R (IX) and CH2R-COPh (X). The absorption spectra of the above compounds have been examined; th a t of VI is nearer the visible than th a t of V, and those of IX and X are nearer the visible than those of the aldehydes V III. Accordingly, from the rules given (loc. cit.) the compounds I —IV would be expected to give a t low temperatures V and a t high temperatures VI, and the compounds V II to give a t low* tem peratures V III and at high temperatures IX and X, and it is found th at, by distillation over infusorial earth a t 200—300° under reduced pressure, V and V III are actually obtained. A t 400—500° the pinacols yield the hydrocarbon which is derived from V or VI by heating, and of which the absorption curve is very much nearer the visible; the glycols V II give ketones or hydrocarbons.
The following new rules are proposed : if isomerides are heated and yield several transposition products, the latter are formed in such a sequence th a t the ultra-violet absorption is displaced towards the visible, provided th a t no carbon radical is lost, and the formation of the various products depends less on the structure of the isomeride than on the tem
The following new rules are proposed : if isomerides are heated and yield several transposition products, the latter are formed in such a sequence th a t the ultra-violet absorption is displaced towards the visible, provided th a t no carbon radical is lost, and the formation of the various products depends less on the structure of the isomeride than on the tem