1-(Benzenesulfonyl)-1H-pyrrolo[2,3-b]pyridine-3-boronic acid pinacol ester

887115-53-9

73183-34-3

886547-94-0

General procedure: 3-iodo-1-(phenylsulfonyl)-1H-pyrrolo[2,3-b]pyridine (4.2 g, 10.9 mmol), bis(pinacolato)diboron (5.6 g, 21.8 mmol), potassium acetate (3.2 g, 32.7 mmol) and Pd(dppf)Cl2-CH2Cl2 (788 mg, 0.982 mmol) The mixture in DMF (40 mL) was placed in a sealed tube and the reaction was stirred at 90 °C for 2 hours. Upon completion of the reaction, the reaction solution was cooled to room temperature, cooled by the addition of ice water, and the pH was adjusted to 12-14 with 6N NaOH solution.Subsequently, the aqueous phase was extracted with dichloromethane (DCM). The aqueous phase was acidified to pH~1 with 6N HCl and then extracted again with DCM several times. All organic phases were combined, dried with anhydrous sodium sulfate (Na2SO4), and concentrated to give 1-benzenesulfonyl pyrrolidinopyridine-3-boronate (4.2 g, quantitative yield) as a brown solid, which could be used in the subsequent reaction without further purification. lCMS analysis showed m/e 386 (boronate M + H)+, 303 (boronic acid M + H)+.