Tetrabutylammonium Fluoride → HCID 57562414, compound

Participants

Reaction Steps

6.15 g of tetrabutylammonium fluoride are added to a solution of 13.4 g of 5-benzyloxy-3-(1-tert-butoxycarbonyl-5-tert-butylsilanyloxy-1H-indol-2-yl)-indazole-1-carboxylic acid tert-butyl ester in 140 ml of tetrahydrofuran. The medium is stirred for 30 minutes at ambient temperature. The reaction crude is washed with 3 times 25 ml of water, the organic phase is then dried over magnesium sulfate and then filtered, and the solvent is evaporated off under reduced pressure in a rotary evaporator. 14.4 g of crude product are obtained, which are purified by flash chromatography (silica 40-63 μm), eluent: dichloromethane/methanol 98:2 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