Chemical Preparations and Drugs. 91 



still adhere to this standpoint. We consider Beilsteins's test as useful only for general 

 guidance, and it seems risky to us to deduce binding conclusions from it in all the 

 cases, as owing to the perceptible volatility of the copper benzoate the flame may be 

 coloured green by the benzoic acid, which would lead to erroneous conclusions 1 ). We 

 would therefore recommend caution when judging benzaldehyde by the result of the 

 copper oxide test. 



As to catalytic reduction of benzaldehyde with copper, and the pyrogenous de- 

 composition of benzaldehyde, see pages 131 and 146 of this Report. 



Benzylalcohol. — According to D. J. Macht and A. T. Shohl 2 ) solutions of benzyl- 

 alcohol keep their anaesthetic qualities unchanged when kept in ampoules of unattackable 

 glass, and their hydrogen ion concentration varies but very showly. On the other 

 hand, in glass which gives off alkali the solutions loss their anaesthetic power quickly 

 and show alkaline reaction in the course of several months. 



J. Messner 3 ) gives the following explanation for the decomposition of benzylalcohol 

 which is said to pass off also in neutral or feebly acid (acetic or hydrochloric acid) 

 solution: — Apparently, reduction as well as oxidation takes place simultaneously, one 

 molecule of the alcohol losing oxygen with formation of toluene, a second molecule 

 absorbing the oxygen liberated with formation of benzaldehyde and water: — 2C e H 5 CH 2 CH 

 = C 6 H 5 CH 3 + C 6 H 5 CHO -f- H 2 0. This reaction may be accelerated by action of light, 

 or owing to the presence of organic or inorganic impurities in the water or the benzyl- 

 alcohol. The latter can even be its own catalyst, as has been proved by Jacobson. 

 Messner strongly disapproves that aqueous solutions of benzalcohol, which decompose 

 easily, be traded in ampoule fillings. 



By heating benzylalcohol, in xylene solution, with barium sulphate -j- palladium 

 K. W. Rosenmund and F. Heise 4 ) obtained 5 per cent, benzaldehyde, 12 per cent, benzyl 

 ether, 50 per cent, benzylalcohol, and 20 per cent, undistillable residue. Pure barium 

 sulphate was of no influence on the alcohol. 



The action of the benzyl esters on the human or the animal organism may be 

 attributed either to the unchanged benzyl ester molecule or to the benzylalcohol formed 

 in the body by hydrolysis of the ester. The fact that benzyl acetate and benzoate are 

 excreted as hippuric acid and that benzylalcohol has a relaxing effect on the unstriped 

 muscle seems to indicate that the effect is due to the hydrolysis of the esters 5 ). Hence, 

 it would be rather probable that the therapeutic effects would be proportional to the 

 rates of hydrolysis of the esters. This possibility induced E. H. Volwiler and E. B. Vliet 6 ) 

 to investigate the chemical part of the problem and to compare the rates of hydrolysis 

 of a number of benzyl ethers. Their experiments, which were conducted according 

 to the directions of Bischoff and Hedenstrom 7 ), proved that the rates of hydrolysis of 

 the esters, under identical conditions, increase in the following order: — salicylate, 

 benzoate, stearate, cinnamate, acetate, succinate, and fumarate. In benzyl acetylsali- 

 cylate, the rate of hydrolysis is of the same order as in benzyl salicylate. 



The authors give a description of the methods employed for the preparation of 

 some of the esters. The preparations had the following constants: — fumarate, m. p. 58.5 



J ) Cf. Kunz-Krause, Apothaker-Zty. 30 (1915), 141. Report October 1915, 56. — 2 ) Journ. ofPharm. arid 

 txper. Therap. 16 (1920), 61. As per Thernp. Halbmonatsh. 35 (1921), 216. — 3 ) Pharm. Zentralh. 03 (1922), 1. 

 - *) Berl. BerichU 54 (1921), 2042. — 6 ) Macht, Journ. Pharmacol. 11 (1918), 263. — 8 ) Joum. Amer. chem. 

 •SV. 43 (1921), 1672. — ') Bert Ben 35 (1902), 3433. 



