Iron(0)-Catalyzed Transfer Hydrogenative Condensation of Nitroarenes with Alcohols: A Straightforward Approach to Benzoxazoles, Benzothiazoles, and Benzimidazoles
作者:Ramachandra Reddy Putta、Simin Chun、Seung Hyun Choi、Seok Beom Lee、Dong-Chan Oh、Suckchang Hong
DOI:10.1021/acs.joc.0c02191
日期:2020.12.4
the redox condensation of o-hydroxynitrobenzene with alcohol, leading to the formation of benzoxazole derivatives. A wide range of 2-substituted benzoxazoles were synthesized in good to excellent yields without the addition of an external redox agent. A series of control experiments provided a plausible mechanism. Furthermore, the reaction system was successfully extended to the synthesis of benzothiazoles
Palladium-catalyzed direct arylation of benzoxazoles with unactivated simple arenes
作者:Ge Wu、Jun Zhou、Min Zhang、Peng Hu、Weiping Su
DOI:10.1039/c2cc34238c
日期:——
Using CuBr(2) as an additive, the Pd-catalyzed intermolecular C-H-C-H cross-coupling between benzoxazoles and unactivated simple arenes has been developed. This protocol provides a straightforward approach for the biological activity of 2-arylbenzoxazole derivatives.
Cu-Catalyzed Synthesis of Benzoxazole with Phenol and Cyclic Oxime
作者:Zheng-Hai Wang、Dong-Hui Wang
DOI:10.1021/acs.orglett.1c04322
日期:2022.1.21
A Cu-catalyzed straightforward synthesis of benzoxazoles from free phenols and cyclic oxime esters is reported. The mild reaction conditions tolerate various electron-withdrawing and electron-donating functional groups on both substrates, affording benzoxazoles in moderate to good yields. With this protocol, large-scale syntheses of Ezutromid and Flunoxaprofe in one or two steps are demonstrated. A