反应详情

To 4-benzhydryl-1-piperazineethanol (18.1 g) was added diketene (5.1 g) and the mixture was heated under stirring at 70°-80° C. for 1.5 hours. The product obtained was purified by silica gel chromatography [eluent: hexaneethyl acetate (3:2)] to give 2-(4-benzhydryl-1-piperazinyl)-ethyl acetoacetate as an oil. Yield 17.1 g (73.6%). IR(Neat): 1730, 1715 cm-1. NMR(CDCl3)δ: 2.22(3H, s), 2.43(10H, broad) 3.39(2H, s), 4.18(1H, s), 4.20(2H, t, J=6), 6.64-7.73(10H, m).

1. temperaturethe mixture was heated
2. customThe product obtained
3. customwas purified by silica gel chromatography [eluent: hexaneethyl acetate (3:2)]