Pinacol → HCID 57537467, compound

Participants

Reaction Steps

Isopropyl magnesium chloride/Li—Cl complex (10.7 ml, 10.9 mmol-14% in THF) was added dropwise to a solution of 5-bromo-4-chloro-3-(2-fluoro-phenyl)-1-(2-trimethylsilanyl-ethoxymethyl)-1H-pyrrolo-[2,3-b]pyridine (2.5 g, 5.4 mmol) under nitrogen in THF at −20° C. The reaction was let to proceed at −20° C. for another 2 hours. Then triisopropyl borate (3.1 ml, 13.6 mmol) in THF was added dropwise and the reaction was continued at −20° C. for another hour. At this time pinacol (1.3 g, 10.9 mmol) was added. The reaction was stirred at room temperature overnight. The solvent was removed under vacuum. Silica chromatography of the crude using a gradient of ethyl acetate and hexane afforded 4-chloro-3-(2-fluoro-phenyl)-5-(4,4,5,5-tetramethyl[1,3,2]-dioxaborolan-2-yl)-1-(2-trimethylsilanyl-ethoxymethyl)-1H-pyrrolo[2,3-b]pyridine (1.0 g, 63% yield). 1H NMR (500 MHz, DMSO-d6) δ 0.01 (s, 9H), 0.94 (t, 2H), 1.58 (s, 12H), 3.69 (t, 2H), 5.81 (s, 2H), 7.40 (m, 2H), 7.56 (m, 2H), 7.99 (s, 1H), 8.40 (m, 1H). MS: m/z 503.2 (M+H+).

Provenance & Evidence