3,5-Dimethylisoxazole-4-boronic acid pinacol ester → HCID 46205511, compound

Participants

Reaction Conditions

Reaction Steps

A mixture of 3,5-dimethyl-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)isoxazole (252 mg, 1.12 mmol), 5-chloro-N-(2,4-difluorophenyl)pyrido[3,2-d]pyridazin-2-amine (300 mg, 1.02 mmol) and tetrakis (36 mg, 31 μmol) in 4.0 mL of dioxane and sodium carbonate (2.0 mL of 1 N solution) was heated in a microwave at 130° C. for 35 min. It was diluted with 10 mL of EtOAc and 2.0 mL water and extracted. An additional extraction with DCM (15 mL) was done. The combined extracts and an insoluble tan solid were dried over MgSO4. Filtration through a sintered glass frit washing with 1:1 MeOH:DCM resulted in complete solubilization of the tan solid. The solution was concentrated and washed with Et2O (2×15 mL), EtOAc (15 mL) and hexanes (2×15 mL) to afford a tan amorphous solid which was purified on the ISCO to afford the title compound as a yellow amorphous solid. MS (ESI, pos.ion) m/z: M+1=354.0

Provenance & Evidence