反应详情

2′-Fluoroacetophenone (25 g, 180 mmol) and (S)-(−)-2-methyl-CBS-oxazaborolidine (6.02 g, 22 mmol) were combined in THF (200 mL). Borane methyl sulfide complex (2M in THF; 59.4 mL, 119 mmol) was added over 20 minutes, and the reaction was stirred at room temperature for 30 minutes. MeOH was added, and the mixture was worked-up with CH2Cl2 and H2O. The organic layer was concentrated to give the title compound in 90.6% e.e., determined by HPLC analysis of the acetate derivative (made by reacting the benzyl alcohol with acetyl chloride and triethylamine in methylene chloride) using Chiralcel OD eluted with 99.8:0.2 Hexanes:EtOH; R isomer retention time 5.9 minutes.

1. concentrationThe organic layer was concentrated