Radical C-H Arylation of Oxazoles with Aryl Iodides: dppf as an Electron-Transfer Mediator for Cs2CO3

Zhengwei Guo; Man Li; Xue-Qing Mou; Gang He; Xiao-Song Xue; Gong Chen

doi:10.1021/acs.orglett.8b00530

Radical C-H Arylation of Oxazoles with Aryl Iodides: dppf as an Electron-Transfer Mediator for Cs₂CO₃

Org Lett. 2018 Mar 16;20(6):1684-1687. doi: 10.1021/acs.orglett.8b00530. Epub 2018 Mar 1.

Authors

Zhengwei Guo¹, Man Li¹, Xue-Qing Mou¹, Gang He^{1

2}, Xiao-Song Xue¹, Gong Chen^{1

2}

Affiliations

¹ State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry , Nankai University , Tianjin 300071 , China.
² Collaborative Innovation Center of Chemical Science and Engineering (Tianjin) , Tianjin 300071 , China.

PMID: 29494163
DOI: 10.1021/acs.orglett.8b00530

Abstract

A radical C-H arylation reaction of oxazoles with (hetero)aryl iodides using Cs₂CO₃ as base/electron donor and 1,1'-bis(diphenylphosphino) ferrocene (dppf) as a catalytic SET mediator is reported. The overall reaction likely follows the general base-promoted homolytic aromatic substitution mechanism through a radical-chain pathway. DFT calculations suggest that dppf forms a complex with CsCO₃^-, enhancing its SET reducing ability to generate an aryl radical from ArI.

Publication types

Research Support, Non-U.S. Gov't