— 162 — Q 



Tanacetophorone. In our last October Report (p. 127) we referred 

 to the reduction of tanacetophorone to 1,3-isopropyl cyclopentanone de- 

 scribed by Wallach. The preparation of tanacetophorone by means of 

 the dry distillation of tanacetonedicarboxylic salto does not yield any 

 particularly favourable results. Wallach 1 ) now states that it is possible 

 by another method to obtain tanacetophorone in a very pure state and in 

 workable quantity. One molecule methyl a-tanacetonedicarboxylate is 

 mixed with a concentrated solution of 1 atom sodium in methylalcohol. 

 The solution is heated for a short period, when it congeals into a yellow 

 crystalline paste, consisting of the sodium compound of isopropyl cyclo- 

 pentenone carboxylic ester. The aqueous solution of the sodium salt is 

 boiled for 1 to 2 hours in a reflux condenser, after which the solution is 

 acidulated with sulphuric acid and distilled with steam. When semicarbazide 

 acetate is added to the distillate tanacetophorone semicarbazone results. 



The sodium salt of tanacetophorone carboxylic acid is readily reducible 

 by Paal's method. When the reduction mixture is diluted with sulphuric 

 acid and distilled with steam, 1,3-^opropylq/cZopentanone passes over 

 (b. p. 188 to 189°; d 2 io 0,9000; n D21c 1,4428; m. p. of the dibenzylidene 

 compound 134 to 135°). When isopropylq/c/opentanone is treated with 

 magnesium methyl iodide, the result is methyl- l-isopropyl-3-q/cfopentanol-l 

 (m. p. 43 to 44°; b. p. 185 to 186°). This alcohol is most probably identical 

 with methyl-tsopropylq/cZopentanol, formed by acting with nitrous acid 

 upon fenchyl alcohol 2 ). 



On the formation of menthol from pulegone see p. 155. 



Phenols and Phenolethers. 



A new method of estimating thymol is described on p. 131. 



Jsoeugenol. E. Puxeddu 3 ) has found that when sunlight is allowed 

 to act upon isoeugenol in alcoholic solution acidulated with hydrochloric 

 acid, about 50 p. c. of the original material is polymerised within about 

 half an hour into dusoeugenol (m. p. 180°). The filtrate was further ex- 

 posed to light, when, in the course of seven days, another 25 p. c. was 

 polymerised. In the same manner dimethyl dk'soeugenol (m. p. 106°) and 

 diethyl diisoeugenol (m. p. 129 to 130°) were produced from methyl- and 

 ethylisoeugenol respectively. Propyk'soeugenol (m. p. 54°) is obtained by 

 acting with propyliodide upon isoeugenol in alkaline solution under 15 hours' 

 heating upon the water-bath; dipropyldk'soeugenol has m. p. 94°. When 



x ) Liebigs Annalen 388 (1912), 49. 



2 ) Comp. Report April 1911, 187. 



3 ) Atti R. Accad. dei Lincei, Roma (5), 21(1912), 1.42, 124. Quoted from Ghem. Zentralbl. 

 1912, I. 809, 910. 



