Dimethylformamide → N-methoxy-N-methyl-3-(methylthio)benzamide

Participants

Reaction Steps

To a stirred solution of 3-(methylthio)benzoic acid (15.4 g, 91.5 mmol), cooled to 0° C. with a brine/ice bath, was added N,N-dimethylformamide (0.35 mL, 4.6 mmol) followed by oxalyl chloride (8.79 mL, 100 mmol). The resulting mixture was stirred 2 h at room temperature, until gas evolution stopped and a clear solution was obtained. The mixture was cooled to 0° C. with a brine/ice bath, N,O-Dimethylhydroxylamine (10.7 g, 110 mmol) was added at once, followed by dropwise addition of triethylamine (43.4 mL, 311 mmol) through a dropping funnel, while keeping the internal temperature under 20° C. The resulting suspension was stirred overnight at room temperature, filtered over a pad of silica gel, and concentrated in vacuo to afford N-methoxy-N-methyl-3-(methylsulfanyl)benzamide as an oil [19.9 g, yield 83%; HPLC/MS: m/z=212 (M+H); logP(HCOOH)=1.89].

Provenance & Evidence