— 199 — 



with 20° o hydrochloric acid or 10°/o caustic soda solution, and of which 

 Thomson has prepared the dimethyl-, diethyl-, di-n-propyl-, di-tsobutyl- and 

 di-?soamyl-esters, all of which formed readily. The dimethyl- and di-ethyl- 

 esters yielded a sodium derivative, among the decomposition products 

 of which were tanacetophorone, 



CsH7vx 



/Mhujadicarboxylic acid 



O , 



C 3 H 7 <. x C0 2 H 



^ C0 2 H 



and an unknown, inactive dicarboxylic acid C 9 Hi 4 4 , m. p. 150 to 151°. 



Phenols and Phenol Ethers. 



Some years ago we mentioned that Brunei *), by reducing thymol and 

 carvacrol according to Sabatier's method, had obtained thymomenthol and 

 carvomenthol. As the reaction had been carried out at a rather high tem- 

 perature (about 160°), and the possibility of a transposition of the iso- 

 propyl group was therefore not excluded, the author 2 ) has recently reversed 

 the reaction by preparing the corresponding phenols from the hydro- 

 aromatic alcohols. By oxidising thymomenthol with chromic acid in an 

 acetic acid solution he obtained thymomenthone which, when brominated, 

 yielded dibromothymomenthone , from which thymol was obtained by 

 reacting with quinoline, and was identified by the formation of aristol 

 (tetrathymoliodide) 3 ). Further, thymomenthol, menthol, and carvomenthol 

 were heated to about 230° with reduced copper, the result being that 

 thymomenthol and menthol yielded thymol, and carvomenthol, carvacrol. 

 The abstraction of hydrogen took place at a much slower rate in the 

 case of carvomenthol than in that of thymomenthol. 



The two reactions described above prove, therefore, that when thymol 

 and carvacrol are reduced, the isopropyl-group undergoes no change. 



The dissertation by C. Guillaumin 4 ) on ortho- and parathymol, to which 

 we referred some time ago, has since then been published in the Bulletin 

 de la Societe chiniique"). 



x ) Compt. rend 137 (1903), 1268; 140 (1905), 252; 141 (1905), 1245, Comp. Report April 1905, 

 103; October 1905, 103; April 1909, 125. 

 2 ) Compt. rend. 150 (1910), 1528. 

 : ) See Beckmann, Berl. Berichte 29 (1896), 418. 

 ±) Comp. Report April 1909, 136. 

 5 ) Bull. Soc. chim. VI. 7 (1910), 332. 



