(NE)-2-methyl-N-[[6-(trifluoromethyl)-3-pyridinyl]methylidene]propane-2-sulfinamide → 2-methyl-N-{(1R)-1-[6-(trifluoromethyl)-3-pyridinyl]ethyl}-2-propanesulfinamide

Participants

Reaction Conditions

Reaction Steps

To a solution of 2-methyl-N-{(1E)-[6-(trifluoromethyl)-3-pyridinyl]methylene}-2-propanesulfinamide (76.8 g, 276 mmol) in dichloromethane (920 mL) at −45° C. was added methylmagnesium bromide (3.0 M in tetrahydrofuran; 184 mL, 552 mmol). The mixture was stirred at −45° C. for 4 h. The reaction mixture was warmed to −20° C. Additional methylmagnesium bromide (3.0 M in tetrahydrofuran; 276 mL, 828 mmol) was added at −20° C. The reaction mixture was warmed to 0° C. and was quenched with saturated aqueous ammonium chloride (300 mL). The mixture was allowed to warm to ambient temperature. The organic layer was separated and the aqueous layer was extracted with dichloromethane (3×). The combined organic extracts were washed with saturated aqueous sodium chloride, dried over magnesium sulfate, filtered and concentrated under reduced pressure. The concentrate was recrystallized using ethyl alcohol (500 mL). The title compound was filtered and dried under reduced pressure (41.6 g). MS 295.0 (M+1).

Provenance & Evidence