Water → 1-Benzyl-3-(3,4-dichlorophenyl)-4-piperidinone

Participants

Reaction Conditions

Reaction Steps

To a solution of sodium hydride (60% in oil, 4.85 g) in toluene (109 mL) was added a solution of the compound (34.6 g) obtained in step 3 in ethanol (25.1 mL), and the mixture was stirred at 75° C. for 2 hr. The reaction mixture was poured into water, and the resultant product was extracted with ethyl acetate. The organic layer was washed with brine and dried, and the solvent was evaporated under reduced pressure. A solution of the obtained residue (30.3 g) in concentrated hydrochloric acid (100 mL) and acetic acid (34 mL) was stirred at 140° C. for 5 hr. The reaction mixture was concentrated under reduced pressure, and the obtained residue was made basic with aqueous sodium hydroxide solution. The resultant product was extracted with ethyl acetate, and the organic layer was washed with brine and dried, and the solvent was evaporated under reduced pressure. The obtained residue was purified by silica gel column chromatography (solvent gradient; 10→50% ethyl acetate/hexane) to give 1-benzyl-3-(3,4-dichlorophenyl)-4-piperidinone (18.2 g, 73%) as a colorless oil.

Provenance & Evidence