Potassium Carbonate → tert-butyl 4-[(4-oxopiperidin-1-yl)methyl]tetrahydro-2H-pyran-4-carboxylate

Participants

Reaction Steps

To a refluxing mixture of tert-butyl 4-(aminomethyl)tetrahydro-2H-pyran-4-carboxylate (8.00 g, 0.0372 mol, step 2) and K2CO3 (0.51 g, 0.0372 mol) in EtOH—H2O (2:1, 240 mL) was added dropwise 1-ethyl-1-methyl-4-oxopiperidinium iodide (12.0 g, 0.0445 mol, J. Org. Chem. 1995, 60, 4324-4330) in EtOH—H2O (2:1, 150 mL), and the resulting mixture was stirred at the same temperature (reflux) for 1 h. After cooling to room temperature, the solvent was removed in vacuo. The residue was poured into sat. NaHCO3 aq. (200 mL), and the mixture was extracted with CH2Cl2 (200 mLx three times). The extracts were dried over Na2SO4 and concentrated. The residue was chromatographed on a column of silica gel eluting with hexane/ethyl acetate (3:1 to 2:1) to give 10.77 g (98%) of the title compound as a colorless syrup.

Provenance & Evidence