tert-Butylsulfinamide, (R)-(+)- → (NZ,R)-N-[1-(5-bromo-2-fluorophenyl)-2-fluoroethylidene]-2-methylpropane-2-sulfinamide

Participants

Reaction Steps

Titanium (IV) ethoxide (4.05 mL, 19.6 mmol) was added via syringe to a solution of 1-(5-bromo-2-fluorophenyl)-2-fluoroethanone (2.3 g, 9.79 mmol) and (R)-(+)-2-methyl-2-propanesulfinamide (2.37 g, 19.57 mmol) in tetrahydrofuran (20 ml) at RT. The reaction was stirred for 18 hours and then the reaction was slowly poured into a vigorously stirred water/EtOAc mixture. After stirring 15 minutes, the mixture was filtered through a Celite pad, which was rinsed with ethyl acetate, and the phases were separated. The aqueous layer was extracted with ethyl acetate; the combined organic extracts were washed with brine, dried over anhydrous sodium sulfate, filtered and concentrated. The crude product was purified by silica-gel chromatography, eluting with 10% EtOAc in hexanes, to provide the title compound (2.81 g, 8.31 mmol, 85% yield) as a yellow oil. LC/MS (ESI+) m/z=338, 340 (M+H; 2 bromine isotopes).

Provenance & Evidence