Phosphorus oxide (P4O10) → 7-Mercapto-4-methylcoumarin

Participants

Reaction Conditions

Reaction Steps

26.3 g (0.1 mol) of S-(4-methyl-2-oxo-2H-1-benzopyran-7-yl) dimethylthiocarbamate are suspended in 300 ml of methanol under a nitrogen atmosphere. 0.2 mol of sodium methylate (8% solution of Na (w/v) in methanol) is added at room temperature and the mixture is heated at 45° C. for 4 hours. The disappearance of the starting material is monitored by thin layer chromatography using an ethyl acetate/toluene mixture (1/4 v/v) as the eluent. After cooling, the reaction medium is hydrolyzed on an ice/concentrated hydrochloric acid mixture and, after stirring for 30 minutes, the precipitate obtained is filtered off and then washed with water. After drying over P2O5, 19.2 g (yield≈100%) of the expected product are obtained.

Provenance & Evidence