Dichloromethane → HCID 57562414, compound

Participants

Reaction Steps

A solution of 13.4 g of 5-benzyloxy-3-[1-tert-butoxycarbonyl-5-(tert-butyl-dimethylsilanyloxy)-1H-indol-2-yl]indazole-1-carboxylic acid tert-butyl ester and 6.15 g of tetrabutylammonium fluoride in 140 ml of anhydrous tetrahydrofuran is stirred at ambient temperature for 30 minutes. The solvent is evaporated off under vacuum. The reaction crude is taken up with 50 ml of dichloromethane and the organic phase is washed with 2 times 25 ml of distilled water. The organic phase is dried over magnesium sulfate. After filtration and concentration under vacuum, the reaction crude is purified by flash chromatography on 450 g of 40-63 μm silica. Elution is carried out with 100% dichloromethane and then a 98/2 then 95/5 dichloromethane/methanol mixture to Obtain 8.54 g of 5-benzyloxy-3-(1-tert-butoxycarbonyl-5-hydroxy-1H-indol-2-yl)indazole-1-carboxylic acid tert-butyl ester.

Provenance & Evidence