tert-Butylsulfinamide, (R)-(+)- → HCID 90373422, compound

Participants

Reaction Conditions

Reaction Steps

To a solution of 1-(2-chloro-3-fluorophenyl)ethanone (31.21 g, 181 mmol) in tetrahydrofuran (500 mL) was added (R)-2-methylpropane-2-sulfinamide (32.9 g, 271 mmol) and titanium(IV) isopropoxide (111 mL, 371 mmol). The mixture was heated to 65° C. overnight. LCMS showed 25% starting material remaining. Additional 16 g sulfinamide and 30 mL Ti(OPr)4 was added and the reaction was continued at 70° C. overnight. The mixture was diluted with brine (600 mL), and EtOAc. The solid was filtered through a pad of celite and washed with EtOAc. The organic layer was washed with brine, dried over sodium sulfate, filtered and concentrated in vacuo. The crude material was purified by silica gel chromatography (330 g, 0-60% EtOAc-hexane in 20 min) to give (R,Z)-N-(1-(2-chloro-3-fluorophenyl)ethylidene)-2-methylpropane-2-sulfinamide (40.8 g, 82% yield) as yellow oil. MS m/z=276 [M+H]+. Calculated for C12H15ClFOS: 275.8.

Provenance & Evidence