(NE,R)-N-[(5-bromo-2-pyridinyl)methylidene]-2-methylpropane-2-sulfinamide → (R)-2-methyl-propane-2-sulfinic acid[(R)-1-(5-bromo-pyridin-2-yl)-ethyl]-amide

Participants

Reaction Conditions

Reaction Steps

A solution of (R)-2-methyl-propane-2-sulfinic acid 1-(5-bromo-pyridin-2-yl)-meth-(E)-ylideneamide (6.04 g, 20.9 mmol) in 100 mL of CH2Cl2 was cooled to −50° C. MeMgBr (10.4 mL, 31.3 mmol, 3M in Et2O) was added slowly dropwise via syringe pump over 1 h. The reaction mixture was stirred at −50° C. for 30 min and then quenched by the addition of 100 mL of satd aqueous NH4Cl solution. The mixture was partitioned between 200 mL of CH2Cl2 and 150 mL of water. The organic phase was washed with 150 mL of brine, dried over Na2SO4, and concentrated. The residue was purified by flash chromatography on silica gel, eluting with 50-90% EtOAc in hexanes, to provide 5.38 g (84%) of (R)-2-methyl-propane-2-sulfinic acid[(R)-1-(5-bromo-pyridin-2-yl)-ethyl]-amide as a white solid.

Provenance & Evidence