DMF-Assisted Radical Cyclization of o-Isocyanodiaryl Ethers via 1,5-Aryl Migration: Construction of 2-Arylbenzoxazoles

Sitian Yuan; Xiaoling Ye; Jingyu Cai; Zhibin Song; Yuxing Tan; Yiyuan Peng; Qiuping Ding

doi:10.1021/acs.joc.1c02806

DMF-Assisted Radical Cyclization of o-Isocyanodiaryl Ethers via 1,5-Aryl Migration: Construction of 2-Arylbenzoxazoles

J Org Chem. 2022 Jan 21;87(2):1485-1492. doi: 10.1021/acs.joc.1c02806. Epub 2021 Dec 30.

Authors

Sitian Yuan¹, Xiaoling Ye¹, Jingyu Cai¹, Zhibin Song¹, Yuxing Tan¹, Yiyuan Peng¹, Qiuping Ding¹

Affiliation

¹ Key Laboratory for Green Chemistry of Jiangxi Province, Key Laboratory of Functional Small Molecules for Ministry of Education, Jiangxi Normal University, 99 Ziyang Avenue, Nanchang 330022, China.

PMID: 34967643
DOI: 10.1021/acs.joc.1c02806

Abstract

A novel DMF-assisted radical cyclization of o-isocyanodiaryl ethers via 1,5-aryl migration has been developed for the synthesis of a series of 2-arylbenzoxazoles by the FeCl₃/TBHP/Et₃N catalytic system in DMF. However, N,N-dimethylbenzo[d]thiazole-2-carboxamide and N,N-dimethylbenzo[d]selenazole-2-carboxamide were obtained from the corresponding substrate 2-isocyanophenyl p-methoxyphenyl thioether and 2-isocyanodiphenyl selenoether under the same conditions. A possible mechanism may involve aryl 1,5-migration and DMF-assisted radical cyclization of o-isocyanodiaryl ethers.