Cp*Co(III)-catalyzed C H amidation of azines with dioxazolones
作者:Yanzhen Huang、Chao Pi、Zhen Tang、Yangjie Wu、Xiuling Cui
DOI:10.1016/j.cclet.2020.08.046
日期:2020.12
Abstract Cp*Co(III)-catalyzed direct C H amidation of azines has been developed. This conversion could proceed smoothly in the absence of external oxidants, acids or bases, with excellent regioselectivity and broad functional group tolerance. CO2 was released as the sole byproduct, thus providing an environmentally benign amidation process. The products obtained are important intermediates in organic
Rhodium(III)-Catalyzed Directed C−H Amidation of <i>N</i>
-Nitrosoanilines and Subsequent Formation of 1,2-Disubstituted Benzimidazoles
作者:Yanyu Chen、Rong Zhang、Qiujun Peng、Lanting Xu、XianHua Pan
DOI:10.1002/asia.201701287
日期:2017.11.2
An efficient rhodium‐catalyzeddirectC−Hamidation of N‐nitrosoanilines with 1,4,2‐dioxazol‐5‐ones as amidating agents has been developed. This method featured mild reaction conditions, a wide substrate scope and satisfactory yields. Besides, the amidated products could be readily converted to pharmaceutically valuable 1,2‐disubstituted benzimidazoles via an HCl‐mediated deprotection/cyclization process
Interweaving Visible‐Light and Iron Catalysis for Nitrene Formation and Transformation with Dioxazolones
作者:Jing‐Jing Tang、Xiaoqiang Yu、Yi Wang、Yoshinori Yamamoto、Ming Bao
DOI:10.1002/anie.202016234
日期:2021.7.19
transfer reactions with dioxazolones for intermolecular C(sp3)-N, N=S, and N=P bond formation are described. These reactions occur with exogenous-ligand-free process and feature satisfactory to excellent yields (up to 99 %), an ample substrate scope (109 examples) under mild reaction conditions. In contrast to intramolecular C−H amidations strategies, an intermolecular regioselective C−H amidation via
Rh(III)- and Zn(II)-Catalyzed Synthesis of Quinazoline <i>N</i>-Oxides via C–H Amidation–Cyclization of Oximes
作者:Qiang Wang、Fen Wang、Xifa Yang、Xukai Zhou、Xingwei Li
DOI:10.1021/acs.orglett.6b03155
日期:2016.12.2
Quinazoline N-oxides have been prepared from simple ketoximes and 1,4,2-dioxazol-5-ones via Rh(III)-catalyzed C–H activation–amidation of the ketoximes and subsequent Zn(II)-catalyzed cyclization. The substrate scope and functional group compatibility were examined. The reaction features relay catalysis by Rh(III) and Zn(II).
Rh(III)-Catalyzed Regioselective Annulations of 3-Arylisoxazolones and 3-Aryl-1,4,2-dioxazol-5-ones with Propargyl Alcohols: Access to 4-Arylisoquinolines and 4-Arylisoquinolones
The Rh(III)-catalyzed dual directing group assisted C–H activation/annulation of 3-arylisoxazolones with propargyl alcohols has been developed, which expands the application scope of isoxazolones in organic synthesis. This protocol also worked well with 3-aryl-1,4,2-dioxazol-5-ones to produce synthetically and biologically important 4-arylisoquinolones.