3-Iodo-1H-pyrrolo[3,2-c]pyridine

Synthesis

General procedure for the synthesis of 3-iodo-5-azaindole from 5-azaindole: Potassium hydroxide (KOH, 10.39 g, 185.5 mmol, 3.8 eq.) was added to a solution of 1H-pyrrolo[3,2-c]pyridine (5.76 g, 48.8 mmol, 1.0 eq.) in N,N-dimethylformamide (DMF, 30 mL). The reaction mixture was stirred at room temperature for 15 minutes. Subsequently, the reaction mixture was cooled to 0°C and a solution of iodine (I2, 12.4 g, 48.8 mmol, 1.0 eq.) in DMF (15 mL) was slowly added. After continuing to stir at room temperature for 15 min, the reaction mixture was poured into water to quench the reaction. The precipitate was separated by filtration and the solid was washed well with deionized water. Finally, the resulting yellow solid was dried under vacuum to afford 3-iodo-1H-pyrrolo[3,2-c]pyridine (9.9 g, 83% yield).

References

[1] Synthesis, 2005, # 20, p. 3581 - 3588
[2] Bioorganic and Medicinal Chemistry Letters, 2013, vol. 23, # 7, p. 2056 - 2060
[3] Patent: WO2018/11628, 2018, A1. Location in patent: Paragraph 00308
[4] Organic and Biomolecular Chemistry, 2011, vol. 9, # 14, p. 5129 - 5136