2,2'-Bipyridine → 1-cyclopropyl-6-fluoro-1H-pyrrolo[2,3-b]pyridine

Participants

Reaction Conditions

Reaction Steps

To a solution of 6-fluoro-1H-pyrrolo[2,3-b]pyridine (6.2 g, 45.55 mmol) in dry DCM (250 mL) is added cyclopropylboronic acid (7.82 g, 91.09 mmol), followed by cupric acetate (8.36 g, 45.55 mmol), sodium carbonate (9.65 g, 91.09 mmol) and 2,2′-bipyridine (7.11 g, 45.55 mmol). The resulting mixture is stirred and heated at 50° C. for 15 h. The mixture is cooled to room temperature and further cupric acetate (4.18 g, 22.77 mmol) and sodium carbonate (2.41 g, 22.77 mmol) are added, followed by cyclopropylboronic acid (1.96 g, 22.77 mmol). The mixture is stirred and heated at 50° C. for a further 15 h when further cupric acetate (1.5 g, 8.25 mmol) and cyclopropylboronic acid (1.49 g, 17.34 mmol) are added. The mixture is stirred at room temperature for 4 days and then poured onto sat. aq. NH4Cl, diluted with water and extracted with DCM. The organic layers are combined, washed with brine, dried (magnesium sulphate) and concentrated in vacuo to give a green oil, which is purified by column chromatography on silica, eluting with DCM, to give the title compound (2.03 g, 11.52 mmol). MS (m/z): 177 (M+1). Unreacted 6-fluoro-1H-pyrrolo[2,3-b]pyridine is also recovered (3.012 g, 22.1 mmol). MS (m/z): 137 (M+1).

Provenance & Evidence