Hydrochloric Acid → 4-(5-carboxy-1-methylindol-3-ylmethyl)-3-methoxy-N-(2-methylphenylsulfonyl)benzamide

Participants

Reaction Conditions

Reaction Steps

A mixture of 4-(5-methoxycarbonyl-1-methylindol-3-ylmethyl)-3-methoxy-N-(2-methylphenylsulfonyl)benzamide (130.0 g), tetrahydrofuran (1.0 L) and 1N sodium hydroxide (1.0 L) was heated to about 60° C. overnight, then treated with additional 1N sodium hydroxide (200 mL) and heated an additional 5 hours at 60° C. (likely unnecessary). The cooled reaction mixture was acidified with 6N hydrochloric acid (250 mL) and extracted with ethyl acetate. The ethyl acetate solution was washed with brine (three times), dried (MgSO4) and evaporated to give a solid which was dried at 50° C. under vacuum to give 4-(5-carboxy-1-methylindol-3-ylmethyl)-3-methoxy-N-(2-methylphenylsulfonyl)benzamide (12.9 g, 100% when calculated as 0.45 hydrate), mp 255°-257° C.; NMR (300 MHz, DMSO-d6): 2.60 (s, 3H, ArCH3), 3.76 (s, 3H, NCH3), 3.91 (s, 3H, OCH3), 4.05 (s, 2H, ArCH2Ar'), 7.15 (d, 1H), 7.19 (s, 1H), 7.39-7.51 (m, 5H), 7.58 (br t, 1H), 7.72 (dd, 1H), 8.03 (dd, 1H), 8.14 (d, 1H).

Provenance & Evidence