60 
YANILLINUM. 
Vanillin. 
C 6 H 3 .OH.OCH 3 .COH 4:3:1 
/CHO (1) 
Methyl ether of protocatechuic aldehyde C 6 H 3 — OCH 3 (3), occurring- 
' ' OH (4) 
natural/ in vanilla or made synthetically. Vanilla (U. S. P.) contains 
from 1 to 2 or 3 per cent of vanillin. 
Eugenol, the principal constituent of oil of cloyes, is allylmethyl 
P3 T rocatechoI, and by oxidation yields yanillin, the allyl group being 
oxidized to the aldehyde group, (CHO), present in yanillin. 
Character. — Colorless, prismatic needles, having the odor and taste 
of vanilla, and melting at 80° to 81 C. 
Solubility. — Soluble in cold water (about 1:100), in warm (1:15), 
easily soluble in alcohol, glycerin, ether, and chloroform. 
Being a phenol in character, it readily dissolves in dilute alkali 
hydroxides, from which it is precipitated by acids. It is extracted 
completely from its solution in ether hy shaking with a saturated 
aqueous solution of sodium bisulphite, from which it may be precipi- 
tated again by sulphuric acid. 
Purity. — The Pharmacopoeia guards against a possible adulteration 
with acetanilide by the following test: on warming 0.1 Gm. of Vanillin 
with concentrated alcoholic solution of sodium hydroxide, adding 
chloroform and again warming it should not give the disgusting odor 
of phenyl isocyanide; such an odor would indicate acetanilide. 
Dose. — 66 Average dose: 0.030 Gm. =30 milligrammes (i grain).” 
(U. S. P.) 
Caution.— Keep in well -stoppered bottles, in a cool place, and pro- 
tected from the light. 
Coumarin 
O-CO 
CH=CH 
the anhydride of orthocinnamic acid 
is an odoriferous principle found in the Tonka bean (1.5 per cent), 
and elsewhere, which resembles vanillin in odor. It forms colorless, 
shining prisms, melting at 67° C., and soluble in 100 parts cold, 45 
parts of hot water, and in 7.5 parts of alcohol, easily soluble in ether. 
“Extracts of vanilla” are sometimes found to be made not from the 
true vanilla bean, but to be alcoholic tinctures of synthetic vanillin or 
coumarin. Such sophistication can readily be detected, as follows: 
If some of the extract be freed from alcohol by evaporation, made up 
to its original volume with water and acidified with acetic acid, a red- 
dish brown precipitate of resin will form in the case of a true extract; 
absence of such resin would indicate an artificial extract. The filtrate 
from this resin, in a true extract, should give a copious precipitate 
with basic lead acetate solution; an artificial gives none. 
