1-(3-Chlorophenyl)ethanone → (R)-1-(3-Chlorophenyl)ethanol

Participants

Reaction Steps

To a solution of borane-tetrahydrofuran (0.647 mL, 0.647 mmol, Aldrich, 1 M solution in THF) and (S)-MeCBS (0.647 mL, 0.647 mmol, Aldrich, 1M solution in toluene) was added simultaneously a solution of 3-chloroacetophenone (1.00 g, 6.47 mmol) in anhydrous tetrahydrofuran (2.42 mL) and a solution of borane-tetrahydrofuran (3.24 mL, 3.24 mmol, Aldrich, 1 M solution in THF) over 30 min at ambient temperature. After complete addition, the reaction mixture was stirred for 10 min, quenched slowly at 0° C. with methanol (0.94 mL) and then saturated HCl in ether (0.12 mL). After stirring at 0° C. for 5 min and ambient temperature for 30 min, the solution was concentrated in vacuo to an oil. The oil was twice diluted with benzene and concentrated in vacuo, diluted with ether, and concentrated in vacuo to an oil. The oil was purified by flash chromatography (silica gel, 20% EA in hexane) to give (R)-1-(3-chlorophenyl)ethanol as a clear colorless oil (0.784 g, 78%). Optical rotation in CHCl3 at 20° C. at concentration 0.220 was +40.90 (Literature, Bull. Chem. Soc. Jpn. 1996, 69(4), 1079-1085, optical rotation in CHCl3 at 21° C. at concentration 0.220 was +44°).

Provenance & Evidence