O,O-Diethyl dithiophosphate → 2-Methyl-3-nitrobenzothioamide

Participants

Reaction Steps

A solution of 2-methyl-3-nitrobenzonitrile (4.85 g, 29.9 mmol) and O,O-diethyl S-hydrogen phosphorodithioate (7.53 mL, 44.9 mmol) in 1,4-dioxane (60 mL) and water (50 mL) was heated at 90° C. for 3 days. During this period, two additional portions of O,O-diethyl S-hydrogen phosphorodithioate (2×7.53 mL, 2×44.9 mmol) were added after every 24 hr. The reaction mixture was concentrated under vacuum to a volume of approximate 60 mL. To the residue was slowly added saturated NaHCO3 solution (80 mL), and the mixture was extracted with ethyl acetate (4×60 mL). The combined extract was washed with saturated NaHCO3 solution (60 mL) and dried over anhydrous MgSO4. The desired product, 2-methyl-3-nitrobenzothioamide (4.58 g, 23.3 mmol, 78% yield) was isolated as a pale solid by ISCO (330 g silica gel, solid loading, 20-30% ethyl acetate/hexane, 45 min).

Provenance & Evidence