2-bromo-N-(tert-butyl)-5-((2-(trimethylsilyl)ethoxy)methyl)-5H-pyrrolo[2,3-b]pyrazine-7-carboxamide → 2-(5-difluoromethoxy-1H-indazol-3-yl)-5-(2-trimethylsilanyl-ethoxymethyl)-5H-pyrrolo[2,3-b]pyrazine-7-carboxylic acid tert-butylamide

関与物質

反応条件

反応手順

In a round-bottomed flask, 2-bromo-5-(2-trimethylsilanyl-ethoxymethyl)-5H-pyrrolo[2,3-b]pyrazine-7-carboxylic acid tert-butylamide (200 mg, 0.47 mmol) and 5-difluoromethoxy-3-tributylstannyl-1H-indazole (crude from Step 1, 509 mg, 0.59 mmol) were dissolved in DMF (3.2 ml). The reaction mixture was evacuated and backfilled with argon then tetrakis(triphenylphosphine)palladium (0) (27.0 mg, 0.023 mmol) and copper (I) iodide (18 mg, 0.095 mmol) were added. The reaction mixture was stirred at 90° C. for 2 h then cooled to room temperature, quenched with water and extracted with ethyl acetate/diethyl ether (2×). The combined organic layers were washed three times with water and once with brine then concentrated. The residue was absorbed on silica gel and chromatographed with EtOAc/dichloromethane (gradient: 0-30% EtOAc). The appropriate fractions were combined and concentrated and the residue was triturated with diethyl ether to afford 158 mg (64%) of 2-(5-difluoromethoxy-1H-indazol-3-yl)-5-(2-trimethylsilanyl-ethoxymethyl)-5H-pyrrolo[2,3-b]pyrazine-7-carboxylic acid tert-butylamide as an off-white powder.

情報源と証拠