Sodium hydride → 1-(Benzyloxycarbonyl)-4-(3-oxo-3-phenylprop-1-enyl)piperidine

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Reaction Steps

Diethyl (2-oxo-2-phenylethyl)phosphonate (0.96 mL, 1.1 g, 4.4 mmol) was added in one portion to a stirred suspension of sodium hydride (60% oil dispersion, 158 mg, 3.95 mmol) in THF (20 mL). After 15 min. at rt, the clear solution was cooled in an ice bath and 1-(benzyloxycarbonyl)-4-piperidinecarboxaldehyde (840 mg, 3.40 mmol) was added in THF (1.0 mL) with additional THF (2×1.0 mL) for rinsing. Stirring was continued for a total of 2 h, with slow warming to rt. The mixture was then partitioned between ether (120 mL) and 2.5 N aq. NaOH (60 mL). The organic layer was washed with saturated aq. brine (60 mL), dried (sodium sulfate), decanted, and evaporated. The crude product was purified by FC, eluting with 15-20% ethyl acetate in hexane, to give 0.95 g of the title compound as a colorless syrup.

Provenance & Evidence