反应详情

To a solution of 1-(4-pyridyl)piperazine (262 mg) and triethylamine (0.1 ml) in acetonitrile (10 ml) was added dropwise over 40 minutes a solution of methyl 5-(2-bromoacetyl)benzofuran-2-carboxylate in acetonitrile (5 ml). The resulting mixture was stirred for 2 hours, concentrated and purified by flash column chromatography on grade III alumina, eluting with methanol/dichloromethane (1:99 to 4:96 v/v) to give the title compound as a solid (138 mg); m.p. 173°-177° C.: NMR 2.66(4H,m), 3.8(4H,m), 3.91(3H,s), 4.00(2H,s), 6.82(2H,m), 7.8-8.5(6H,m); m/e 380 (M+H+); calculated for C21H21N3O4.0.5H2O: C, 64.9; H, 5.7; N, 10.8. Found: C, 65.2; H, 5.7; N, 10.9%. The starting ester was prepared as follows:

1. concentrationconcentrated
2. custompurified by flash column chromatography on grade III alumina
3. washeluting with methanol/dichloromethane (1:99 to 4:96 v/v)