反应详情

106 ml of a 4N ethyl acetate solution of hydrogen chloride were added, whilst ice-cooling, to a solution of 27.50 g of (3R)-1-t-butoxycarbonyl-3-(4-methoxybenzylthio)pyrrolidine [prepared as described in step (2) above] dissolved in 100 ml of ethyl acetate, and the mixture was stirred at 0° to 5° C. for 30 minutes and then at 25° C. for 2 hours. At the end of this time, the mixture was diluted with 200 ml of diisopropyl ether, and the crystals which precipitated were collected by filtration, to give 20.84 g of the title compound as colorless crystals, melting at 125°-126° C.

1. waitat 25° C. for 2 hours
2. customthe crystals which precipitated
3. filtrationwere collected by filtration