反应详情

A solution of methyl 4-[5-[2-carboxy-1-hydroxy-3-(propylcarbamoyl)propyl]-1-propylindol-3-ylmethyl]-3-methoxybenzoate (0.81 g), and N,N-dimethylformamide di-tert-butyl acetal (1.54 ml, redistilled) in methylene chloride (26 ml) was stirred under a nitrogen atmosphere for 1 hour. The solvent was evaporated, and the product purified by flash chromatography, eluting with 4:1 ethyl acetate: hexane, to give methyl 3-methoxy-4-[1-propyl-5-[3-(propylcarbamoyl)prop-1-enyl]indol-3-ylmethyl]benzoate (0.56 g, 79%, as a separable mixture of olefin isomers) as a white solid: mp 140°-142°; E-olefin partial NMR (300 MHz, DMSO-d6): 0.83(m, 6H, 2×CH3), 3.82(s, 3H, OCH3), 3.92(s, 3H, OCH3). 6.15(d of t, 1H, olefinic-H), 6.47(d, J=15.9 Hz, 1H, olefinic-H), 7.86(t, 1H, NH), Z-olefin partial NMR (300 MHz, DMSO-d6 ): 0.82(m, 6H, 2×CH3), 3.82(s, 3H, OCH3), 3.90(s, 3H, OCH3), 5.70(m, 1H, olefinic-H), 6.57(d, J=11.5 HZ, 1H, olefinic-H), 7.86(t, 1H, NH).

1. customThe solvent was evaporated
2. customthe product purified by flash chromatography
3. washeluting with 4:1 ethyl acetate