1,2-Dibromoethane → 3-cyclobutyl-1-(phenylsulfonyl)-1H-pyrrolo[2,3-b]pyridine

Participants

Reaction Steps

A round bottom flask under a nitrogen atmosphere was charged with magnesium turnings (155 mg, 6.38 mmol) and dry ether (5 mL). Bromocyclobutane (340 mg, 2.52 mmol) was added, followed by 1,2-dibromoethane (50 μL) and refluxing was observed after a few minutes of stirring. This mixture was then warmed back to reflux for 5 hours and then allowed to cool to room temperature. The Grignard reagent was then added to a THF solution (5 mL) of 3-bromo-1-(phenylsulfonyl)-1H-pyrrolo[2,3-b]pyridine (250 mg, 0.74 mmol) and NiCl2(dppf) (10 mg, 0.015 mmol). The mixture was heated at reflux for 16 hours and then allowed to cool to room temperature. The reaction mixture was quenched with saturated ammonium chloride solution and extracted with EtOAc (2×). The extracts were dried over sodium sulfate and concentrated. Flash 40 Biotage (40M cartridge, 3:1 hexane:EtOAc) afforded 3-cyclobutyl-1-(phenylsulfonyl)-1H-pyrrolo[2,3-b]pyridine (45 mg, 19%). m/z (APCI-pos) M+1=313.1.

Provenance & Evidence