Potassium Carbonate → 4-((3-cyclopropyl-4-nitro-1H-indazol-1-yl)methyl)-2-methyloxazole

Participants

Reaction Steps

A 25 mL round bottom flask equipped with a reflux condenser and a nitrogen line was charged with 4-((3-bromo-4-nitro-1H-indazol-1-yl)methyl)-2-methyloxazole (304 mg, 0.902 mmol), cyclopropylboronic acid (170 mg, 1.98 mmol), palladium acetate (8 mg, 0.036 mmol), potassium carbonate (410 mg, 2.98 mmol), and sodium 2′-(dicyclohexylphosphino)-2,6-dimethoxybiphenyl-3-sulfonate (37 mg, 0.072 mmol). To the flask was added a 1,4-dioxane:water mixture (5:1; 6 mL), and the flask was evacuated and refilled with nitrogen three times. The reaction mixture was stirred and heated at reflux for 11 hours. The reaction mixture was cooled, diluted with excess water and extracted multiple times with DCM and EtOAc. The combined organic extracts were dried over anhydrous sodium sulfate, concentrated, and subjected to preparative thin-layer chromatography (silica, 1:1 EtOAc/Hexane as eluent) to afford the product (88.1 mg) as a solid.

Provenance & Evidence