Water → Tert-butyl 4-(3-hydroxybenzylidene)piperidine-1-carboxylate

Participants

Reaction Conditions

Reaction Steps

To a solution of tert-butyl 4-(bromomethylene)piperidine-1-carboxylate (38 g, 0.1376 mol) in dry THF (380 mL) was added 3-hydroxyphenyl boronic acid (22.77 g, 0.165 mol), potassium phosphate (88.2 g, 0.415 mol) and water (7.6 mL). The mixture was degassed with argon. 1,1′-Bis(diphenylphosphino)ferrocene palladium(II) dichloride dichloromethane complex (11.23 g, 0.01376 mol) was added and the mixture was degassed again. The reaction was heated at 50° C. for 1.5 h and then allowed to cool to RT. Water was added and the mixture was extracted with ethyl acetate (3×). The total organic extract was washed with brine, dried over sodium sulfate and evaporated to dryness. The residue was purified by silica gel chromatography using 100-200 mesh silica gel (8% ethyl acetate in hexane) to give the title compound (26.3 g, 66%). 1H NMR (500 MHz, CDCl3): δ 7.16 (t, J=7.5 Hz, 1H), 6.74 (d, J=7.5 Hz, 1H), 6.68 (d, J=9 Hz, 1H), 6.68 (s, 1H), 6.30 (s, 1H), 5.37 (bs, 1H), 3.49 (m, 2H), 3.40 (m, 2H), 2.46 (m, 2H), 2.31 (m, 2H), 1.48 (s, 9H); 13C NMR (125 MHz, CDCl3): δ 156.09, 155.09, 138.87, 138.15, 129.31, 124.58, 120.98, 115.74, 113.54, 80.10, 45.45, 44.57, 36.08, 29.23, 28.50.

Provenance & Evidence