反应详情

A solution of (R) 3-(4-tert-butoxycarbonylamino-phenyl)-3-[(5-methyl-isoxazole-3-carbonyl)-amino]-propionic acid tert-butyl ester (2 g, Reference Example 11) in dichloromethane (50 mL) was treated with trifluoroacetic acid (5 mL). After four hours [the reaction was monitored by TLC: no more starting material was visible after about 4 hours] at room temperature the reaction mixture was poured carefully onto a mixture of sodium hydrogen carbonate solution (100 mL, 5% w/v) and dichloromethane (50 mL). The organic layer was separated then dried and then evaporated to give the title compound (1.0 g) as a yellow oil which slowly crystallised on standing.

1. waitno more starting material was visible after about 4 hours
2. customThe organic layer was separated
3. customthen dried
4. customevaporated