Dimethylformamide → (R)-3-(N-Benzyloxycarbonylpyrrolidin-2-ylmethyl)-7-bromo-5-(methylaminosulfonylmethyl)-1H-indole

Participants

Reaction Conditions

Reaction Steps

(R)-1-(N-Benzyloxycarbonylpyrrolidin-2-yl)-3-[N-(4-methylaminosulfonylmethyl-2,6-dibromophenyl)-N-trifluoroacetylamino]propene (9.00 g) in triethylamine (70 mL) containing N,N-dimethylformamide (20 mL), tetra-n-butylammonium chloride (3.61 g) and palladium acetate (1.01 g) was heated at 80° C. until conversion was complete. The cooled reaction mixture was filtered through CELITE and washed with methylene chloride. The combined filtrate and washings were then evaporated in vacuo onto silica gel (15 g) then purified by column chromatography (SiO2--1.6 kg) eluted with 4% acetone in chloroform. The product-rich fractions were combined and evaporated then re-purified by crystallisation from a mixture of diethyl ether (50 mL) and methylene chloride (10 mL). The title compound was recovered by filtration (washing with hexanes) as a colorless solid (2.40 g). TLC (methylene chloride/acetone 10:1) Rf=0.35; Anal calcd. for C23H26BrN3O4S: C, 53.1; H, 5.0; N, 8.1. Found C, 53.13; H, 5.0; N, 7.8.

Provenance & Evidence