Diisopropylamine → Methyl 3-(prop-1-en-2-yl)-1-(thiophen-3-yl)-1H-indazole-6-carboxylate

Participants

Reaction Conditions

Reaction Steps

Methyl 3-bromo-1-(thiophen-3-yl)-1H-indazole-6-carboxylate (1.414 g, 4.19 mmol), 2-isopropenyl-4,4,5,5-tetramethyl-1,3,2-dioxaborolane (1.58 ml, 8.41 mmol), diisopropylamine (1.18 ml, 8.40 mmol), triphenylphosphine-3,3′,3″-trisulfonic acid trisodium salt hydrate (275.8 mg, 0.431 mmol), and palladium(II) acetate (48.3 mg, 0.215 mmol) were dissolved in N,N-dimethylformamide (15 ml)/water (5 mL), placed in a sealed tube and heated to 100° C. for 4 h. The reaction was stopped, cooled to room temperature, quenched by addition of saturated aqueous ammonium chloride (20 mL), and the mixture extracted with ethyl acetate (3×20 mL). The combined organic phases were washed with saturated aqueous sodium chloride (1×15 mL), dried (sodium sulfate), filtered, and the solvent evaporated under reduced pressure. The crude product was purified by flash chromatography (RediSep SiO2, 330 g column) on a CombiFlash Rf purification system eluting with ethyl acetate-hexanes (0-15%). The title compound (1.0847 g, 3.64 mmol, 87% yield) was recovered as a white solid. LC-MS: [M+1]=299.2.

Provenance & Evidence