Asymmetric reduction of chloroacetophenone using a sulfoximine catalyst

4 ASYMMETRIC REDUCTION OF CHLOROACETOPHENONE USING A SULFOXIMINE CATALYST S] 

A 50 mL two-necked flask equipped with a magnetic stirrer bar was dried overnight at 150°C, cooled under vacuum and flushed with nitrogen. 

Under a nitrogen atmosphere, the flask was charged with (S S)-methyl-S-phenylsulfoximine (523 mg) and placed under vacuum. The flask was flushed with nitrogen, then dry acetonitrile (15mL), and N, 9-bis-(tri-methylsilyl)-acetamide (924 pL) were added. 

The flask was equipped with a condenser and the mixture was heated under nitrogen at 50 °C and stirred for 45 minutes at this temperature (it was not necessary for the solvent to reflux). 

After 45 minutes, the mixture was cooled to room temperature under nitrogen. The solvent was evaporated under high vacuum. 

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