反应详情

Tetrahydropyran-4-carbonyl chloride was added drop wise to a mixture of piperazine-1,3-dicarboxylicacid 1-tert-butyl ester (123 g, Reference Example 63) and triethylamine (150 g) in dichloromethane (2000 ml) over a period of 0.45 hours. After stirring at room temperature for 3 days the reaction mixture was treated with water (1500 ml) and then acidified to pH 2 by addition of hydrochloric acid (37%). The organic phase was separated, then washed with aqueous sodium chloride solution (1%) and then evaporated under reduced pressure to give a yellow foam (157 g) which was recrystallised from diethyl ether and then from ethyl acetate to give the title compound (67.9 g) as white solid.

1. customThe organic phase was separated
2. washwashed with aqueous sodium chloride solution (1%)
3. customevaporated under reduced pressure