2-Propenoic acid, 3-(1H-indol-3-yl)-, ethyl ester → 3-(1H-Indol-6-yl)-3-(1H-indol-3-yl)-acrylic acid ethyl ester

Participants

Reaction Conditions

Reaction Steps

A sealed tube flushed with N2 was charged with 3-(1H-indol-3-yl)-acrylic acid ethyl ester (323 mg, 1.5 mmol), 6-bromoindole (196 mg, 1 mmol), tetra-butylammonium bromide (64.4 mg, 0.2 mmol), TEA (209 μl, 1.5 mmol) and palladium-dichloro-[bis(tri-ortho-tolyl)phosphine] (39.3 mg, 0.05 mmol). The mixture was stirred at 114° C. for 1 hour, cooled to room temperature, dissolved in DCM, and purified via flash chromatography (hexane/EtOAc) to afford 3-(1H-indol-6-yl)-3-(1H-indol-3-yl)-acrylic acid ethyl ester XXVI (250 mg, yellow oil) as a mixture of geometric isomers.

Provenance & Evidence