BENZOIN. 239 
balsamic smell; insoluble in water, soluble in alcohol and ether ; 
boils at 198°°5 C. at 761 millim., and at 199°-2 at 746 millim. ; 
its sp. gr. is 1:10 at 17° and 1:0876 at 16° C. (Kopp). Its consti- 
tution is represented by the formula C,H,O,. According to 
another authority methyl benzoate is conveniently prepared by 
passing hydrochloric acid into a solution of benzoic acid in methy] 
alcohol, distillmg, and then precipitating the ether with water *. 
Ethy! benzoate was prepared by Scheele as long ago as 1785, by 
the distillation of a mixture of alcohol, benzoic acid, and hydro- 
ehloric acid. It is not formed when an alcoholic solution of the 
acid is allowed to stand in the cold, but the ether is gradually 
formed if a little hydrochloric acid be added, or if the liquid be 
heated to 100°. The method adopted for the preparation of 
methyl benzoate may be followed, or it may be prepared by distil- 
lng four parts of alcohol with two parts of benzoic acid and one 
part of fuming hydrochloric acid till two-thirds have passed over, 
and pouring back the distillate into the retort two or three times, 
a little of the ether passes over, but the greater part remains in the 
residue, whence it is separated by the addition of water. It isalso 
obtained when a solution of three parts of benzoic acid in two 
parts of boiling alcohol of 80 per cent. is heated for some time in 
a vessel provided with a reflux condenser. It is represented by the 
formula, CyH,,)Q.. 
It is also readily formed by the action of benzoyl chloride 
(C;H;OCl) on alcohol, which is very susceptible of its presence. 
The presence of alcohol even in very dilute aqueous solution can 
therefore be detected by warming it with a little benzoyl chloride, 
and removing the excess of this acid by caustic soda; even when 
only 0-1 per cent. of alcohol is present, the characteristic odour 
of ethyl benzoate can be distinctly recognized (Berthelot). 
Isonitrosobenzyl ether, C,H;CH,ON, is prepared by heating 
benzyl chloride (C;H,Cl) with a solution of sodium and isonitroso- 
acetone in absolute alcohol. It crystallizes from petroleum ether 
in colourless tablets, which have a pleasant smell of flowers. It 
melts at 45° to 46° +. 
Benzoylacetone is formed together with acetophenone and ben- 
zoic acid when benzoylacetic acid is boiled with water{. It is 
* Ann, Chem, Pharm. cx. p. 210. 
+ Ber. Deutsch. chem. Ges. xv. p. 3071. 
t Ibid. xvi. p. 2239, 
