Water → HCID 10759909, compound

Participants

Reaction Steps

N-tert-Butyloxycarbonyl-4-piperidone (5 g), 2-phenylpiperidine (4.03 g) and titanium isopropoxide (8.9 ml) were stirred at room temperature under a nitrogen atmosphere for 3 h. The resulting orange solution was diluted with methanol (40 ml), treated with sodium cyanoborohydride (1.6 g), and stirred for 20 h. Water (50 ml) was added to give a granular precipitate which was removed by filtration through celite. The filtrate was partitioned between water-ethyl acetate, the organic phase separated, dried (MgSO4) and concentrated. The residue was dissolved in ethyl acetate and washed with a saturated aqueous solution of citric acid. The aqueous phase was basified to pH10 using 4N sodium hydroxide, and extracted into ethyl acetate. The organic phase was dried (MgSO4) and concentrated. The residue was chromatographed using ethyl acetate-petroleum ether (20:80 to 50:50) to afford a partially purified mixture, which was dissolved in ethyl acetate. The organic phase was washed with a saturated aqueous solution of citric acid. The aqueous phase was separated, basified to pH10 using 4N sodium hydroxide and extracted with ethyl acetate. The organic phase was dried (MgSO4) and concentrated to give the product in 3% yield. δH (250 MHz, CDCl3) 1.16-1.79 (19H, m), 2.21-2.29 (2H, m), 2.41-2.50 (2H, m), 2.90-3.04 (1H, m), 3.36-3.44 (1H, m), 3.92-4.10 (2H, m), 7.16-7.40 (5H, m).

Provenance & Evidence