Acetic Acid → 4-(Benzylamino)cyclohexan-1-one

Participants

Reaction Steps

To a suspension of 1,4-dioxaspiro[4.5]decan-8-one (10 g, 64.0 mmol) in DCE (200 mL) was added phenylmethanamine (7.34 mL, 67.2 mmol), AcOH (3.67 mL, 64.0 mmol) and sodium triacetoxyborohydride (19.00 g, 90 mmol). The reaction was stirred at RT for 16 hours and then the mixture was diluted with 1N NaOH (100 mL) and DCM (250 mL). The organic layer was collected, dried over sodium sulfate and concentrated under reduced pressure. The residue was suspended in acetone (66.7 mL) and treated with HCl (2N aqueous) (64.0 mL, 128 mmol), and the mixture was stirred at RT for 16 hours. The reaction mixture was concentrated to half its volume and diluted with 1 N aqueous NaOH (100 mL) and DCM (300 mL). The layers were separated, and the organic portion was dried over sodium sulfate and concentrated under reduced pressure to afford a white solid. The solid was purified by silica gel chromatography (5-10% MeOH/DCM) to afford 4-(benzylamino)cyclohexanone (9.1 g, 69.9% yield). MS m/z=204.2 [M+H]. Calc'd for C13H17NO: 203.1.

Provenance & Evidence