反应详情

(S)-Piperidine-1,3-dicarboxylic acid 1-benzyl ester (XXXII) (12.0 g, 45.6 mmol) was taken in neat oxalyl chloride (30 ml), 0.2 mL of DMF was added and the mixture was stirred at room temperature for 1 hour. Completion of the reaction was monitored by TLC which showed the formation of a non-polar spot after treatment of a small amount with methanol. Then the reaction mixture was concentrated under reduced pressure to provide (S)-3-chlorocarbonyl-piperidine-1-carboxylic acid benzyl ester (XXXIII) (12.66 g) which was directly used in the next reaction.

1. concentrationThen the reaction mixture was concentrated under reduced pressure