Dicyclohexylcarbodiimide → t-Butyl 5-{[5-(2-pyridyldithiomethyl)benzofuran-2-ylcarbonyl]amino}indole-2-carboxylate

Participants

Reaction Steps

A stirred solution of 15 (247 mg, 0.78 mmol) in 30 mL dry THF at room temperature under argon, was treated sequentially with solutions of dicyclohexylcarbodiimide (177 mg, 0.86 mmol) in 5 mL methylene chloride, 4-(dimethylamino)pyridine (29 mg, 0.23 mmol) in 2 mL methylene chloride, and 10 (200 mg, 0.86 mmol) in 5 mL methylene chloride. The reaction mixture was stirred overnight. Dicyclohexylurea was filtered from the reaction mixture, and the filtrate was washed with water, cold 0.1M HCl, saturated aqueous sodium bicarbonate, and water. The organic solution was dried over magnesium sulfate, filtered, and concentrated to give a dark oil. The crude product was further purified by chromatography on a silica gel column, eluting with ethyl acetate:hexanes to give 16 as an off-white solid: NMR (acetone-d6) δ 1.6 (s, 9H), δ 4.3 (s, 2H), δ 7.0-8.6 (m, 12H).

Provenance & Evidence