Ethanol → 4-Azaindole

Participants

Reaction Conditions

Reaction Steps

To a 25 mL microwave vial was added 2-bromo-5H-pyrrolo[2,3-b]pyrazine (0.5 g, 2.52 mmol), 2-fluoropyridin-3-ylboronic acid (600 mg, 4.26 mmol) and sodium carbonate (803 mg, 7.57 mmol) in dioxane (10.0 ml), water (5.00 ml), and EtOH (2.5 ml). The reaction mixture was bubbled through with argon for 10 mins. Pd(PPh3)4 (292 mg, 0.252 mmol). The reaction was bubbled through with argon for 5 mins. The vial was capped and heated in the microwave at 140° C. for 15 min. The reaction mixture was diluted with EtOAc and water. The combined organics were separated, dried (MgSO4), filtered and concentrated. The crude residue dissolved in DCM and treated with silica. The solvent was evaporated and the crude absorbed in silica was purified by SiO2 chromatography eluting with EtOAc/hexane gradient (0% to 60%) to afford 410 mg (76%) of pyrrolopyridine as a light yellow solid. MS m/z (ES): 215 (M+H)+.

Provenance & Evidence