5-Bromo-1-triisopropylsilanyl-1H-pyrrolo[2,3-b]pyridine

13154-24-0

858116-66-2

General procedure for the synthesis of 1-triisopropylsilyl-5-bromo-7-azaindole from triisopropylchlorosilane: Sodium hydride (0.63 g, 25.15 mmol) was added batchwise to a stirred solution of tetrahydrofuran (THF, 50 mL) of 5-bromo-7-azaindole (3.3 g, 16.75 mmol) at room temperature with continuous stirring for 15 min. Subsequently, triisopropylchlorosilane (5.3 mL, 25.15 mmol) was added and the reaction mixture was heated to 80 °C and maintained for 3 hours. After completion of the reaction, the solvent was removed by evaporation and the residue was dissolved in water (50 mL). The aqueous layer was extracted with ethyl acetate (EtOAc, 3 x 50 mL) and the organic phase was dried with anhydrous sodium sulfate (Na2SO4) and concentrated under reduced pressure. The crude product was purified by Biotage HPFC system (eluent: 10% ethyl acetate/hexane) to afford the target compound 5-bromo-1-(triisopropylsilyl)-1H-pyrrolo[2,3-b]pyridine as a white solid (5.2 g, 88% yield). Mass spectrometry analysis showed the molecular ion peak m/z 355 (M + 1).