Sodium Bicarbonate → 4-(6-nitro-1H-indol-3-yl)-benzonitrile

Participants

Reaction Steps

Add 100 mL of 1 M TBAF in THF to a slurry of 4-(1-benzenesulfonyl-6-nitro-1H-indol-3-yl)-benzonitrile 8 (14.3 g, 35 mmol) in 50 mL of THF. Monitor the reaction by TLC. If starting material remains add more 1 M TBAF in THF until the reaction is complete. Pour reaction mixture into 200 mL of saturated aqueous sodium bicarbonate and then extract the resulting solution 3× with EtOAc. Combine the organic extracts and wash the extracts with saturated aqueous bicarbonate, water (2×), brine. Dry the resulting organic solution over Na2SO4, filter, and then remove the organic solvent to provide a solid. Redisolve the solid in ˜400 mL of acetone with heating and then add ˜100 mL hexanes until a precipitate forms. Let the solution cool and then collect the precipitate. Concentrate the filtrates and redisolve in ˜300 mL of 50% acetone/hexanes with heating. Let the solution cool and then place in a freezer at −20° C. overnight. Collect the crystals that form. The combined yield of the title compound is 6.71 g, 25.5 mmol, 72%. LRMS (API ES−)=262.0 (M−1).

Provenance & Evidence