Cesium carbonate → 3-(2,6-Dichlorophenyl)-5-(1-methylethyl)-4-({[4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl]oxy}methyl)isoxazole

Participants

Reaction Conditions

Reaction Steps

Cesium carbonate (1.96 g, 6.03 mmol) was added to 4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-phenol (1.26 g, 5.74 mmol) and 4-(chloromethyl)-3-(2,6-dichlorophenyl)-5-(1-methylethyl)isoxazole (1.75 g, 5.74 mmol) in N,N-dimethylformamide (57 mL) at room temperature. The resulting suspension was heated for sixty-nine hours at 60° C. The reaction was cooled and concentrated to remove the N,N-dimethylformamide, then water was added and the reaction mixture was extracted with diethyl ether. The organic layer was dried over anhydrous magnesium sulfate, then filtered and concentrated. The residue was purified by silica gel chromatography eluting with 1:6 ethyl acetate:hexanes to give 2.24 g (80%) of 3-(2,6-dichlorophenyl)-5-(1-methylethyl)-4-({[4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl]oxy}methyl)isoxazole as an solid. 1H NMR (400 MHz, d6-DMSO): δ 7.62-7.59 (m, 2H), 7.55-7.48 (m, 3H), 6.76 (d, J=9 Hz, 2H), 4.82 (s, 2H), 3.44 (septet, J=7 Hz, 1H), 1.31 (d, J=7 Hz, 6H), 1.24 (s, 12H). ESI-LCMS m/z 488 (M+H)+.

Provenance & Evidence