Cesium fluoride → 4-(4,4'-Dichlorobiphenyl-3-yl)-2,2,6,6-tetramethylpyran-3,5-dione

Participants

Reaction Conditions

Reaction Steps

A mixture of 4-(5-bromo-2-chlorophenyl)-2,2,6,6-tetramethylpyran-3,5-dione (0.22 g, 0.6 mmol), 4-chlorophenylboronic acid (0.14 g, 0.9 mmol), and cesium fluoride (0.28 g, 1.8 mmol) are stirred together in 1,2-dimethoxyethane (2.4 ml) under an atmosphere of nitrogen at room temperature for 45 minutes. [1,1′-bis(diphenyl-phosphino)ferrocene]dichloropalladium(II) (80 mg, 0.098 mmol) is added and the reaction mixture is heated at 80° C. overnight. The reaction mixture is filtered through diatomaceous earth, washing the filter cake with dichloromethane (7 ml) and water (3 ml). The mixture is acidified to pH1 by addition of 2M aqueous hydrochloric acid, and the organic phase is separated. The aqueous phase is extracted with dichloromethane, and all organic extracts are combined, dried over anhydrous magnesium sulfate, filtered and the filtrate evaporated. The residue is dissolved in N,N-dimethylformamide (approximately 1 ml) and purified by preparative reverse phase HPLC to give 4-(4,4′-dichlorobiphenyl-3-yl)-2,2,6,6-tetramethylpyran-3,5-dione (80 mg).

Provenance & Evidence