反应详情

354 mg (1.7 mmol) of 4-(2-methoxycarbonylethyl)benzoic acid (Example 3b) and 500 mg (1.7 mmol) of tert-butyl (2S)-2-benzyloxycarbonylamino-3-amino-propionate were dissolved in 3 ml of DMF and treated with 557 mg (1.7 mmol) of O-[[(cyano(ethoxycarbonyl)methylidene)amino]-1,1,3,3,-tetramethyluronium tetrafluoroborate (TOTU) and 204 mg (1.7 mmol) of diisopropylethylamine (DIPEA) and the solution was stirred at RT for 7 h. The solvent was evaporated in vacuo, the residue was dissolved in ethyl acetate (EA) and washed three times each with KHSO4 and NaHCO3 solution until neutral, the organic phase was separated off and dried, and the solvent was distilled off in vacuo. Yield: 770 mg (93%). MS: ES+, m/e=485.2 (M+H+, 100%)

1. customThe solvent was evaporated in vacuo
2. dissolutionthe residue was dissolved in ethyl acetate (EA)
3. washwashed three times each with KHSO4 and NaHCO3 solution until neutral, the organic phase
4. customwas separated off
5. customdried
6. distillationthe solvent was distilled off in vacuo