Potassium Carbonate → HCID 67120058, compound

Participants

Reaction Steps

A mixture of 4-bromo-5-(2-(tert-butyldimethylsilyloxy)ethyl)-3-(4-methoxyphenyl)-1-methyl-1-H-pyrazole (140 mg, 0.33 mmol), 3,5-dimethylisoxazol-4-ylboronic acid (92.8 mg, 0.66 mmol), K2CO3 (328 mg, 2.37 mmol) and Pd(PPh3)4 (19.0 mg, 0.02 mmol) in DME (1 mL) and water (1 mL) was flushed with argon and irradiated in the microwave at 140° C. for 20 min. Full conversion was not achieved. The mixture was filtered to remove palladium black. Irradiation in the microwave was continued until full conversion was achieved. Altogether 3,5-dimethylisoxazol-4-ylboronic acid (233 mg, 1.66 mmol) and Pd(PPh3)4 (57.0 mg, 0.06 mmol) were used and three irradiations were run. Water was added and the crude mixture was extracted with EtOAc. Purification on silica gel gave 4-(5-(2-(tert-butyldimethylsilyloxy)ethyl)-3-(4-methoxyphenyl)-1-methyl-1H-pyrazol-4-yl)-3,5-dimethylisoxazole (34.4 mg, 0.078 mmol, 24%).

Provenance & Evidence