Tris(4-fluorophenyl)phosphine → 5-Fluoro-1H-pyrrolo[2,3-b]pyridine

Participants

Reaction Conditions

Reaction Steps

A solution of 3-ethynyl-5-fluoro-pyridin-2-ylamine (1.25 g, 9.2 mmol) in DMF (20 mL) is treated with (Rh(cod)2Cl)2 (23 mg, 0.023 mmol) and tris-(4-fluoro-phenyl)-phosphane (115 mg, 0.368 mmol) and stirred at 85° C. for 0.5 h. The mixture is then poured over brine (50 mL), and extracted with EtOAc (3×50 mL). The combined organic layer is dried (Na2SO4), filtered and concentrated in vacuo. The residue is purified by silica gel chromatography eluting with 35%-75% EtOAc in heptane to afford 5-fluoro-1H-pyrrolo[2,3-b]pyridine (1.05 g, 84%). MS: 137 (M+H); 1H NMR (300 MHz, CDCl3): δ 9.15 (s, NH, 1H), 7.99 (s, 1H), 7.44 (d, 1H), 7.18 (s, 1H), 6.28 (s, 1H).

Provenance & Evidence