— 187 — 



According to a communication by G. von Fersen 1 ), when 4 g. magnesium 

 and 20 g. allyl bromide are allowed to act upon 251 g. pulegone, the 

 result is allyl-3-pulegol (methyl- 1 -allyl -3-isopropene- 4- q/cZohexenol -3). 

 This is a viscous, colourless liquid with an odour reminding of peppermint, 

 and possessing the following constants: b. p. 135 to 135,5° (27 mm.), 

 d 2 i, 95 o 0,9264, n D21l95 o 1,49039. 



On the reduction of carvone and eucarvone, see p. 165. 



Phenols and Phenolethers. 



An investigation which has been carried out by H. Stevignon 2 ) gives, 

 inter alia, a description of certain phenol piperazines to which we will 

 briefly refer, as it may possibly serve for the identification of the phenols 

 in question. They are: o-dicresol piperazine, m. p. 51 to 52°, dicarvacrol 

 piperazine, m. p. 85 to 86°, and dithymol piperazine, m. p. 88°. All these 

 piperazines are readily obtainable by evaporating an alcoholic solution of 

 phenol and piperazine on a water-bath; they dissolve readily in the usual 

 organic solvents. 



- Another derivative, possibly serviceable for the identification of car- 

 vacrol, is carvacrol phthaleine, which is prepared by a process devised 

 by C. Ehrlich 3 ) by heating phthalic anhydride and carvacrol with chloride 

 of zinc for 2 hours to. 100°. Carvacrol phthaleine, recrystallised from 

 glacial acetic acid, occurs in colourless crystals, insoluble in water, 

 m. p. 246 to 247°. In soda solution it dissolves with a deep-blue colo- 

 ration. Carvacrol phthaleine is used medicinally as a purgative and has 

 the advantage over phenol phthaleine and thymol phthaleine of being a 

 non-irritant and of having a sustained and uniform action. 



Thymol. The results of the pharmacological investigation of the iso- 

 merides of thymol which have been discovered by Guillaumin, and upon 

 which we have already commented in one of our previous Reports 4 ) 

 have now been published elsewhere 5 ). 



Pasonol. Among the phenols, insoluble in alkalies, which are described 

 by A. Torrey and R. Adams 6 ) are certain derivatives of paeonol, a body which 

 is found in the root of Pceonia Moutan, Sims. The p-nitrophenylhydrazone 

 of this body and of its bromoderivative is soluble in alkalies, but not the 

 m- and o-nitrophenylhydrazones. These very interesting compounds 

 possess the following properties: pseonol- p-nitrophenylhydrazone, brick- 



x ) journ. russ. phys. chem. Ges. 42 (1910), 681. Quoted from Chem. Zentralbl. 1910, II. 1535. 



2 ) Bull. Soc. chim. IV. 7 (1910), 922. 



3 ) German Patent 225983. Chem. Ztg. Rep. 34 (1910), 509. 



4 ) Comp. Report April 1909, 136. 



5 ) Bull. Sciences pharm. 17 (1910), 373. Quoted from Chem. Zentralbl. 1910, II. 1049. 



6 ) Berl. Berichte 43 (1909), 3227. 



