tert-Butylsulfinamide, (R)-(+)- → (NE,R)-N-[[4-(1,1-difluoroethyl)-2-fluorophenyl]methylidene]-2-methylpropane-2-sulfinamide

Participants

Reaction Conditions

Reaction Steps

To a mixture of 4-(1,1-difluoroethyl)-2-fluorobenzaldehyde (693 mg, from Step 4) and (R)-2-methylpropane-2-sulfinamide (513 mg, 4.24 mmol) in DCE (12.9 mL) was added copper(II) sulfate (882 mg, 5.52 mmol). The reaction mixture was placed in a pre-heated oil bath (55° C.) and heated for ˜2 d. The mixture was allowed to cool to room temperature, filtered through a pad of celite and rinsed with DCE. The combined filtrates were concentrated under reduced pressure. The residue was purified by column chromatography [SiO2, 24 g, heptane/ethyl acetate] providing (R,E)-N-(4-(1,1-difluoroethyl)-2-fluorobenzylidene)-2-methylpropane-2-sulfinamide (497 mg) as a yellow oil. LCMS m/z 292.1 (M+H)+, Rt 0.97 min.

Provenance & Evidence