Cesium carbonate → 4-(3-Benzyl-2-cyano-5-methyl-benzofuran-7-yl)-piperazine-1-carboxylic acid tert-butyl ester

Participants

Reaction Conditions

Reaction Steps

In an oven dried flask was added BINAP (racemic, 0.17 g, 0.913 mmol), cesium carbonate (0.35 g, 1.07 mmol), tris(dibenzylideneacetone)dipalladium (0.0207 g, 0.0226 mmol), 1-BOC-piperazine (0.17 g, 0.913 mmol) and 5 ml DMF. The flask was evacuated and refilled with nitrogen. 3-benzyl-7-bromo-5-methyl-benzofuran-2-carbonitrile (0.29 g, 0.90 mmol) in 5 ml DMF was added via syringe and the mixture heated to 80° C. overnight, then to 100° C. for another 24 hours. The mixture was concentrated on a rotary evaporator and purified by column chromatography (1:9 ethyl acetate/hexane) to give 4-(3-benzyl-2-cyano-5-methyl-benzofuran-7-yl)-piperazine-1-carboxylic acid tert-butyl ester (0.174 g, 45% yield) as a yellow solid.

Provenance & Evidence