Imidazole → 2-{6,6-dimethyl-1-[2-(trimethylsilyl)ethoxymethyl]-4,5,6,7-tetrahydro-1H-indazol-3-yl}-1-[2-(trimethylsilyl)ethoxymethyl]-1H-indole-6-carboxylic acid [2-(tert-butyldiphenylsilyloxy)-1-methylethyl]amide

Participants

Reaction Steps

To a solution of 2-{6,6-dimethyl-1-[2-(trimethylsilyl)ethoxymethyl]-4,5,6,7-tetrahydro-1H-indazol-3-yl}-1-[2-(trimethylsilyl)ethoxymethyl]-1H-indole-6-carboxylic acid (2-hydroxy-1-methylethyl)amide (265 mg, 0.42 mmol) in N,N-dimethylformamide (2.7 ml) were added imidazole (35 mg, 0.51 mmol) and tert-butyldiphenylsilyl chloride (132 μl, 0.51 mmol) under ice-cooling, and the mixture was stirred at room temperature for 8 hr. Then, to the reaction mixture were added water and ethyl acetate, and the organic layer was separated. Then, the organic layer was washed successively with water and saturated brine, and dried over sodium sulfate. Sodium sulfate was removed by filtration, and the filtrate was concentrated under reduced pressure. The residue was purified by silica gel chromatography to give the title compound (341 mg, yield 93%).

Provenance & Evidence