A mixture of (5-bromo-1-(2-trimethylsilanyl-ethoxymethyl)-1H-pyrrolo[2,3-b]pyridine 5.0 g, 15.3 mmol), bis(pinacolato)diboron (7.8 g, 30.6 mmol), dichloro[1,1′-bis(diphenylphosphino)ferrocene]palladium(II) dichloromethane adduct (559 mg, 0.8 mmol), and sodium acetate (3.8, 45.8 mmol) in DMF (20 ml) was stirred at 95° C. overnight. The mixture was allowed to cool down to room temperature and then extracted with ethyl acetate (3×). The combined organic layers were extracted with brine, dried with Na2SO4, decanted, and concentrated to dryness. Silica chromatography of the crude using a gradient of ethyl acetate and hexane afforded 5-(4,4,5,5)-tetramethyl[1,3,2]dioxa-borolan-2-yl)-1-(2-trimethylsilanyl-ethoxymethyl)-1H-pyrrolo[2,3-b]pyridine (5.0 g, 88% yield). 1H NMR (500 MHz, DMSO-d6) δ 0.02 (s, 9H), 0.95 (, 2H), 1.45 (s, 2H), 3.65 (m, 2H), 5.75 (s, 2H), 6.70 (s, 1H), 7.75 (s, 1H), 8.40 (s, 1H), 8.60 (s, 1H). MS: m/z 375.2 (M+H+).
