C32 H2 O Az O2
Before it was known to him, Wackenroder, Johnston, Gardeke and Maclagan analyzed this plant without succeeding in the isolation of its active principle.
Some important works undertaken on this subject by Lassen, Humann and R. Pérey are also quoted.
Properties.—Cocaine is colorless, odorless, and bitter to the taste. It crystallizes in the shape of oblique rhomboid prisms of from four to six facets.
It is very soluble in water, less soluble in alcohol, and absolutely insoluble in ether. It does not vaporize below 98°, but if the temperature is greatly increased it is decomposed. It possesses a strongly alkaline reaction.
United with acids it forms salts which are very difficult to crystallize.
Those which have been obtained from it are: the salicylate, oxalate, hydrobromide, sulphate, acetate, and finally the hydrochlorate, which forms an exception to the general rule, and is obtained more easily in the crystalline form than any other.
The solutions of the salts of Cocaine are precipitated by the caustic alkalies, carbonate of sodium, carbonate of ammonium, the alkaline bicarbonates, the bichloride of mercury, the protochloride of tin, bichloride of platinum, and by ammonia, which, added in excess, redissolves the precipitate formed by it. Iodine water, iodized potassium iodide, and picric acid precipitate the solutions of salts of Cocaine. When Cocaine is heated to 100° in a sealed tube with concentrated hydrochloric acid, it separates into benzoic acid and a new base, for which M. Wœhler has proposed the name of Ecgonine. Lassen has discovered another nitrogenous base resulting from the separation of Cocaine—hygrine.
Preparation.—The process used by Niemann for obtaining Cocaine is as follows: