indium(III)chloride → (S)-N-((S)-1-(4-Chloropyridin-2-yl)but-3-enyl)-2-methylpropane-2-sulfinamide

Participants

Reaction Steps

To a cooled (0-5° C.) mixture of indium(III) chloride (13.56 g, 61.3 mmol) in THF (170 mL) was added allylmagnesium bromide (1M in diethylether) (62 mL, 61.3 mmol) dropwise over 30 min. The reaction was allowed to warm to rt. After 1 h at rt, a solution of 45A (10 g, 40.9 mmol) in ethanol (170 mL) was added. After 2-3 h, the reaction was concentrated under vacuum at 50-55° C. The crude material was partitioned between ethyl acetate (200 ml) and water (1×50 ml) and the layers were separated. The aqueous layer was extracted with ethyl acetate (2×50 ml). The organic layers were combined and washed with brine (1×100 ml), dried over sodium sulfate, filtered and concentrated to give 45B (13.5 g, 106%) as a yellow oil. MS (ESI) m/z: 287.2 (M+H)+. This material was used in the next step without further purification.

Provenance & Evidence