Piperonal → HCID 20578938, compound

Participants

Reaction Steps

A solution of the crude amine (9b) (140 mg) prepared above, piperonal (74 mg, 0.49 mmol) and glacial acetic acid (2 drops) in 1,2-dichloroethane (0.5 mL) was stirred for 30 min at room temperature. 95% Sodium cyanoborohydride (32 mg, 0.48 mmol) was added in small portions and stirring was continued for 1 h. The reaction was quenched with saturated aqueous sodium bicarbonate solution (2 mL), extracted with dichloromethane, dried (MgSO4) and evaporated under reduced pressure. The residue was purified by silica gel column chromatography eluting with dichloromethane-ethyl acetate (90:10-75:25) to give the title pyrrole (10) (115 mg, 71.4%) as a pale yellow oil:

Provenance & Evidence