Water → Ethyl-2-methyl-3,4-dihydro-3-oxo-2H-1,4-benzothiazine-2-carboxylate

Participants

Reaction Steps

To a suspension of KF (3.016 g, 52 mmoles) in anhydrous dimethyl formamide (14 ml), diethyl-2-bromo-2-methyl-malonate (3.90 ml, 20 mmoles) was added and the mixture was stirred for 15 minutes at room temperature. Subsequently, 2-mercaptoaniline (2.50 g, 20 mmoles) was added and the mixture was stirred for 6 hours at the temperature of 60° C. and overnight at room temperature. The reaction mixture was admixed with a mixture of water and ice (80 ml), the product which separated was filtered off by suction and recrystallized from absolute ethanol. Thus there were obtained 3.80 g (75.7%) of the title product in the form of white crystals, m.p. 109°-111° C.

Provenance & Evidence