反应详情

To a solution of 4-benzyloxycarbonylamino-cyclohexanecarboxylic acid (8.0 g, 28.78 mmol) in DCM (35 mL) and DMF (35 mL) is added t-butanol (10 mL, 105.4 mmol) and DMAP (1.4 g, 11.50 mmol). DIPC (10 mL) is added portionwise over 1 h. The resulting mixtures stirs 18 h. The mixture is mounted onto SiO2 and purified by flash chromatography (gradient elution: 0-60% EtOAc/Hep) which affords 5.2 g of 4-benzyloxycarbonylamino-cyclohexanecarboxylic acid tert-butyl ester. 1H NMR (400 MHz, DMSO-D6) δ ppm 1.14 (m, 2 H) 1.30 (m, 2 H) 1.38 (m, 9 H) 1.82 (m, 4 H) 2.07 (m, 1 H) 3.20 (m, 1 H) 3.47 (m, 3 H) 4.99 (m, 2 H) 7.27 (m, 5 H).

1. customThe resulting mixtures stirs 18 h
2. custompurified by flash chromatography (gradient elution: 0-60% EtOAc/Hep) which