反应详情

To a solution of 3-methoxy-4-[5-(4,4,4-trifluoro-2-methyl-butylcarbamoyl)-1H-indol-3-ylmethyl]-benzoic acid (1.54 grams, 3.43 mmol), triphenylphosphine (1.26 grams, 4.8 mmol) and benzyl alcohol (0.50 mL, 4.8 mmol) in tetrahydrofuran (50 mL), at 0° C., was added diethyl azodicarboxylate (0.65 mL, 4.1 mmol). The reaction is then warmed to room temperature and stirred 12 hours. Concentration in vacuo followed by chromatography on silica gel (1:1 hexanes:ethyl acetate) gave 3-methoxy-4-[5-(4,4,4-trifluoro-2-methyl-butylcarbamoyl)-1H-indol-3-ylmethyl]-benzoic acid benzylester with impurities present. The product was dissolved in cold ether, and filtered. The filtrate was concentrated, and the remaining yellow foam was chromatographed on silica gel (1:1 cyclohexane:ethyl acetate) to give 3-methoxy-4-[5-(4,4,4-trifluoro-2-methyl-butylcarbamoyl)-1H-indol-3-ylmethyl]-benzoic acid benzylester (1.56 grams, 87% yield).

1. concentrationConcentration in vacuo