Pyridine → E 7820

Participants

Reaction Steps

To a solution of 7-amino-3-cyano-4-methyl-1H-indole (10 g, 58.4 mmol) in tetrahydrofuran (200 ml) were added pyridine (20 ml) and 3-cyanobenzenesulfonyl chloride (12.5 g), followed by stirring at room temperature for 3.5 hours. After further adding 2N hydrochloric acid (100 ml), extraction was performed with ethyl acetate. The organic layer was washed with water (twice) and brine in that order, dried over anhydrous magnesium sulfate, and then concentrated under reduced pressure. The residue was purified by silica gel column chromatography (hexane:ethyl acetate=2:1-3:2). A mixed solvent of ethanol-hexane (1:2) was added thereto, and after sonication, the precipitate was collected by filtration and washed with a mixed solvent of ethanol-hexane (1:3). The mixture was dried overnight under reduced pressure to give the title compound (9.33 g, 27.7 mmol, 47% yield).

Provenance & Evidence