Water → 2-Bromo-4-formyl-3-hydroxy-8-methoxy-1,9-dimethyl-11-oxo-11h-dibenzo[b,e][1,4]dioxepine-6-carboxylic acid

Participants

Reaction Steps

To a solution of psoromic acid (1 mmol) in glacial acetic acid (5 ml) was dropwise added a solution of bromine (3 mmol, 0.15 ml) in glacial acetic acid (3 ml). After stirring at room temperature for several hours, the redbrown reaction mixture was poured into water (50 ml), extracted with ethyl acetate (100 ml), dried with MgSO4, filtered, and evaporated by a rotatory evaporator to give a redbrown solid.

Provenance & Evidence