Abstract Benzothiazol-2-yl glyoxylic acid and α-amino-benzothiazol-2-yl acetic acid hydrochloride undergo decarboxylation at room temperature. This facile decarboxylation seems to depend on the following requirements:(a) the formation of a planar zwitterion;(b) a distance of about 2.2 Å between the charges of the zwitterion;(c) the stabilisation of the intermediate carbanion.
