反应详情

To a solution of 4-amino-1-benzylpiperidine (1.47 g, 7.7 mmol) in CF3CH2OH (14 ml) were added molecular sieve 4 Å (5 g), and paraformaldehyde (0.51 g, 17 mmol). After stirring at RT for 1 h, NaCNBH3 (2.5 g, 39.8 mmol) was added and stirred for 16 h at RT. The reaction was stopped by addition of H2O and the product was extracted with (4:1) (Et2O:CH2Cl2). Organic fractions were combined and washed with brine (2×), dried over MgSO4, filtered and concentrated to give a crude material which was purified by silica flash chromatography to afford 4-dimethylamino-1-benzylpiperidine (80% yield). FAB Mass [M+1]+35Cl 219.

1. stirringstirred for 16 h at RT
2. extractionthe product was extracted with (4:1) (Et2O:CH2Cl2)
3. washwashed with brine (2×)
4. dry with materialdried over MgSO4
5. filtrationfiltered
6. concentrationconcentrated
7. customto give a crude material which
8. customwas purified by silica flash chromatography