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

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

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.

Herkunft & Nachweise