HYACINTH. 99 
chlorethylene on boiling with water or on standing in the cold with 
sodium carbonate solution *. 
Also: a-Phenylbromethylene or phenylvinylbromide is formed 
when phenyldibromopropionic acid is boiled with water. In 
order to prepare this acid, cinnamic acid is dissolved in carbon 
disulphide and a solution of bromine in carbon disulphide gradu- 
ally added, the acid being thus precipitated. It forms small plates 
which readily dissolve in ether and melt at 195°. On boiling with 
water, phenylbromolactic acid, cinnamic acid, a#-phenylbrom- 
ethylene and carbon dioxide are formed. This decomposition is 
brought about by cold sodium-carbonate solution, but is delayed 
by an excess of this reagent. Phenylbromethylene is an oily 
liquid having a pleasant odour resembling that of hyacinths, as 
does also the phenylchlorethylene above described. The former 
boils at 219°-221° (a small quantity of hydrobromic acid being 
evolved) ; the latter compound boils at 199°+. The odour of 
hyacinths is also noticed intensely in a compound called cinny! 
alcohol, which is prepared from styracin (see Storax). Cinnyl 
alcohol, CyH,,O, was formerly called Styrone, Hydrate of cinnyl, 
Cinnamic alcohol, Styracone, and Storax alcohol. 
As indicated by Toel ¢, cinnyl alcohol is obtained by cautiously 
distilling styracin with a strong solution of caustic potash or soda. 
A milky liquid then passes over, from which, when saturated with 
common salt, a creamy substance separates, gradually collecting on 
the surface in an oily layer and solidifying. 
Wolff § dissolves styracin in boiling alcoholic potash, mixes 
water with the liquid, filters from potassium cinnamate, and 
separates the precipitated cinnamic alcohol from undecomposed 
styracin by distillation. Pure cinnyl alcohol forms beautiful soft, 
silky needles, having a sweet taste and an odour of hyacinths. 
It melts at 33° C., and volatilizes without alteration at 250°C. It 
is moderately soluble in water, very soluble in alcohol, in ether, in 
styrol, and in oils both fixed and volatile. 
It has recently been indicated that the chief constituent of the 
non-aldehydes in cassia-oil is the acetic ether of cinnamyl. It can 
be separated by submitting the non-aldehyde portion of cassia-oil 
* Ber. Deutsch. chem. Ges. xiv. p. 1867. 
+ Ann. Chem. Pharm. excy. p. 140, and cevi. p, 33. 
q° Hid! isexspa de 
§ Ibid. lxxxy. p. 299. 
