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
precursors in reactions with thioethers under the catalysis of a commercially available Ru(II) complex, from which a variety of sulfimides were synthesized efficiently and mildly. If an allyl group is contained in the thioether precursor, the [2,3]-sigmatropic rearrangement of the sulfimide occurs simultaneously and the N-allyl-N-(thio)amides were obtained as the final products. Preliminary mechanistic studies
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
Angeli−Rimini's Reaction on Solid Support: A New Approach to Hydroxamic Acids
作者:Andrea Porcheddu、Giampaolo Giacomelli
DOI:10.1021/jo061018g
日期:2006.9.1
Angeli−Rimini's reaction has been performed for the first time on solid phase. A convenient one-step procedure for the synthesis of hydroxamicacids starting from aldehydes and solid-supported N-hydroxybenzenesulfonamide is reported. The hydroxamates are isolated in good to high yields and purities by simple evaporation of the volatile solvents, after treatment of the crude reaction mixture with sequestering