反应详情

Tert-butyl 4-{5-[2-fluoro-4-(1H-tetrazol-1-yl)phenyl]benzo[d]oxazol-2-yl}piperidine-1-carboxylate (250 mg, 0.54 mmol) dissolved in DCM (15 ml) and added Trifluoroacetic acid (1 ml). This mixture was stirred at rt for 2 h. DCM removed from the reaction mixture to obtain 5-[2-fluoro-4-(1H-tetrazol-1-yl)phenyl]-2-(piperidin-4-yl)benzo[d]oxazole 2,2,2-trifluoroacetate (260 mg). 5-[2-fluoro-4-(1H-tetrazol-1-yl)phenyl]-2-(piperidin-4-yl)benzo[d]oxazole 2,2,2-trifluoroacetate (150 mg, 0.31 mmol) was dissolved in DMF (2.6 ml) and added N,N-Carbonyl diimidazole (101 mg, 0.63 mmol) and stirred at rt for 1 h. To this mixture added 3-pentanol (46 mg, 0.63 mmol) and TEA (0.13 ml, 0.94 mmol) and stirred at 60° C. for overnight. Work up (EtOAc/H2O) and purification of the crude by combiflash with gradient mixture of ethyl acetate and petether (1:1) as eluent afforded the titled compound (20 mg) as an off-white solid. M.P.: 114-117° C. 1H-NMR (δ ppm, CDCl3, 400 MHz): 9.03 (s, 1H), 7.88 (s, 1H), 7.72-7.58 (m, 4H), 7.54-7.50 (m, 1H), 4.69 (quintet, J 6, 1H), 4.23 (d, J 13.5, 2H), 3.25-3.15 (m, 1H), 3.07 (t, J 11.9, 2H), 2.21-2.17 (m, 2H), 2.02-1.88 (m, 2H), 1.65-1.50 (m, 4H), 0.91 (t, J 7.4, 6H).

1. customDCM removed from the reaction mixture