反应详情

To a stirred solution of 1-(4-Methyl-benzo[b]thiophen-3-ylmethyl)-1,3-dihydro-benzimidazol-2-one (50 mg, 0.17 mmol), 3-Hydroxy-2,2-dimethyl-propionic acid methyl ester (0.026 mL, 0.20 mmol) and triphenylphosphine (53 mg, 0.20 mmol) in dry THF (1.5 mL) is added diisopropyl azodicarboxylate (0.041 mL, 0.20 mmol) in a drop wise manner. The mixture is stirred at room temperature for 40 hrs. Then the solvent is removed under vacuum and the residue is purified by two preparative TLC's (first one is developed with 30% EtOAc in Hexanes, second one is developed with 1% MeOH in CH2Cl2) to give 28 mg (41%) of 2,2-Dimethyl-3-[3-(4-methyl-benzo[b]thiophen-3-ylmethyl)-2-oxo-2,3-dihydro-benzimidazol-1-yl]-propionic acid methyl ester.

1. customThen the solvent is removed under vacuum
2. customthe residue is purified by two preparative TLC's (first one is developed with 30% EtOAc in Hexanes, second one is developed with 1% MeOH in CH2Cl2)