Ethyl Acetate → Ethyl 2-carbamothioyl-2-methylacetate

Participants

Reaction Steps

A mixture of diphenylphosphinodithioic acid (ALFAAESAR, 37.4 g, 149 mmol) and 2-cyanopropionic acid ethyl ester (ABCR, 9.90 mL, 74.7 mmol) in isopropanol (350 mL) was heated under reflux for 5 h. TLC (Hex:EtOAc 7:3) showed reaction had gone to completion. Reaction mixture was allowed to cool and was placed in the fridge overnight. Reaction mixture was filtered off and washed with isopropanol. Residue was partitioned between ethyl acetate (250 mL) and 1N NaOH (250 mL). Phases were separated and organic phase was washed with water (300 mL), brine (300 mL), dried over sodium sulfate and concentrated to dryness. Crude was purified by chromatography on silica gel using a hexane/EtOAc gradient. Appropriate fractions were combined and evaporated to yield title compound as a white solid (6.6 g, 40.9 mmol, 54.8% yield). 1H NMR (300 MHz, DMSO-d6) δ ppm: 9.60 (s, 1H), 9.40 (s, 1H), 4.05 (q, 2H), 3.74 (q, 1H), 1.29 (d, 3H), 1.15 (t, 3H). [ES+MS] m/z 162 (MH+).

Provenance & Evidence