反应详情

Step 1): A solution of 1-diphenylmethylpiperidine-4-carboxamide (14.79 g, 50 mmol) in POCl3 (300 ml) was refluxed for 3.5 hours. The reaction mixture was concentrated under vacuum. The residue was dissolved into the mixture of sat. NaHCO3 aq. solution and AcOEt. After separation, the aqueous layer was extracted with AcOEt. The combined organic layer was washed with H2O and brine, dried over MgSO4 and then concentrated. The residue was recrystallized from iso-PrOH to give 4-cyano-1-diphenylmethylpiperidine, 12.36 g (89%): mp 219°-230° C.

1. concentrationThe reaction mixture was concentrated under vacuum
2. dissolutionThe residue was dissolved into the mixture of sat. NaHCO3 aq. solution and AcOEt
3. customAfter separation
4. extractionthe aqueous layer was extracted with AcOEt
5. washThe combined organic layer was washed with H2O and brine
6. dry with materialdried over MgSO4
7. concentrationconcentrated
8. customThe residue was recrystallized from iso-PrOH