catechol ( pyrocatechin, pyrocatechol )
A colorless crystal (C 6 H 6
O 2 ), soluble in water, alcohol,
ether, benzene, and alkalis. An alkaline solution
gives a coloration with ferric chloride, which
turns brown on standing in air. It can be obtained
fromCATECHU , a
natural dye, or prepared by fusing
orthobenzenedisulfonic acid with caustic soda.
Catechol is the principal constituent of the
condensed (catechol) tannins. See also: VEGETABLE TANNINS .
(235 , 306 )