反应详情

5-Benzylamino-3,6-dihydro-2H-pyridine-1,4-dicarboxylic acid 1-tert-butyl ester 4-ethyl ester. 3-Oxo-piperidine-1,4-dicarboxylic acid 1-tert-butyl ester 4-ethyl ester (8.15 g, 30 mmol) from Step A and benzyl amine (3.43 g, 31.8 mmol) were dissolved into toluene (150 mL). The mixture was refluxed vigorously for 72 h and the generated water was collected into Dean-Stark apparatus. The residual solution was concentrated to yield the title compound (10.2 g, 92.5%). MS (ESI) mass calcd. for C20H28N2O4, 360.45, m/z found, 361.2 [M+H]+. The crude product was carried to the next step without any purification.

1. temperatureThe mixture was refluxed vigorously for 72 h
2. customthe generated water was collected into Dean-Stark apparatus
3. concentrationThe residual solution was concentrated