Solvent/Oxidant-Switchable Synthesis of Multisubstituted Quinazolines and Benzimidazoles via Metal-Free Selective Oxidative Annulation of Arylamidines

Jian-Ping Lin, Feng-Hua Zhang and Ya-Qiu Long*

*CAS Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zuchongzhi Road, Shanghai 201203, China, Email: yqlongsimm.ac.cn

J.-P. Lin, F.-H. Zhang, Y.-Q. Long, Org. Lett., 2014, 16, 2822-2825.

DOI: 10.1021/ol500864r (free Supporting Information)

---

see article for more reactions

Abstract

A fast and simple reaction of amidines gave benzimidazoles via iodine(III)-promoted oxidative C(sp³)-C(sp²) bond formation in nonpolar solvents, whereas the use of polar solvents favoured a C(sp²)-N bond formation to yield quinazolines. Further selective synthesis of quinazolines in polar solvent was realized using TEMPO as catalyst and K₂S₂O₈ as the oxidant. No metal, base, or other additives were needed.

see article for more examples

---

---

Key Words

Quinazolines, Benzimidazoles, PIDA, TEMPO, Potassium peroxydisulfate

---

ID: J54-Y2014