Acetic Acid → (3-Cyano-4-oxo-4H-1-benzopyran-6-yl)methylene diacetate

Participants

Reaction Steps

To a solution of 9.25 parts of 6-methyl-4-oxo-4H-1-benzopyran-3-carbonitrile in a mixture of 100 parts by volume of acetic acid, 100 parts by volume of acetic anhydride and 10 parts by volume of 97% sulfuric acid kept at 5°-10° C, there was added 15.5 parts of chromium trioxide over a period of 4 hours under stirring. The reaction mixture was poured into 1500 parts by volume of ice-water to give precipitates, which were collected by filtration, washed with water and recrystallized from ethanol. The procedure yielded 8.19 parts of 6-diacetoxymethyl-4-oxo-4H-1-benzopyran-3-carbonitrile as colorless needles. Melting point: 185°-186° C

Provenance & Evidence