Transition‐Metal‐Free Radical Cyclization of 2‐Arylbenzoimidazoles with Unactivated Alkanes via C(sp3)−H Functionalizations in Aqueous Media

• Published in: Advanced synthesis & catalysis Vol. 364; no. 12; pp. 2080 - 2085
• Main Authors: Li, Jiao‐Zhe, Mei, Lan, Cai, Xue‐Er, Zhang, Can‐Can, Cao, Ting‐Ting, Huang, Xun‐Jie, Liu, Yi‐Lin, Wei, Wen‐Ting
• Format: Journal Article
• Language: English
• Published: WEINHEIM Wiley 21.06.2022; Wiley Subscription Services, Inc
• Subjects: Alkanes; aqueous media; Aqueous solutions; C(sp3)−H functionalizations; Chemistry; Chemistry, Applied; Chemistry, Organic; Free radicals; Hydrogen bonds; Physical Sciences; radical cyclization; Science & Technology; Toluene; transition-metal-free; CATALYSIS; radical cyclization; C(sp)-H functionalizations; ACIDS; transition-metal-free; aqueous media; ACRYLAMIDES; CASCADE CYCLIZATION; WATER
• ISSN: 1615-4150; 1615-4169
• DOI: 10.1002/adsc.202200272

Here we present a transition‐metal‐free radical cyclization of 2‐arylbenzoimidazoles with unactivated alkanes. By using di‐tert‐butyl peroxide (DTBP) to promote the C(sp3)−H bond functionalization, this approach enables assembly of various benzimidazo[2,1‐a]isoquinolin‐6(5H)‐ones in aqueous media. This strategy can not only well tolerate a wide range of cyclic alkanes, straight‐chain alkanes, toluene derivatives, as well as pharmaceutical molecule eudesmol, but also provides an approach for the functionalization of unactivated C(sp3)−H bonds in aqueous media under transition‐metal‐free systems.