Low Catalyst Loadings for Ligand-Free Copper(I)-Oxide-Catalyzed<i>N</i>-Arylation of Methanesulfonamide in Water
作者:Bryan Yong-Hao Tan、Yong-Chua Teo、Ai-Hua Seow
DOI:10.1002/ejoc.201301561
日期:2014.3
A simple and practical protocol for the cross-coupling of methanesulfonamide and aryl iodides under ligand-freecopper(I)-oxide-catalyzed conditions in water is reported. The method allows the preparation of a wide variety of synthetically useful N-arylated methanesulfonamides in good to excellent yields (up to 90 %) under the optimized conditions.
efficient approach to access an array of diverse unsymmetrical diaryl and heterodiaryl sulfones, aryl alkyl sulfones and aryl vinyl sulfones in good to excellent yields. An alternative approach with eco-friendliness and high efficiency for the preparation of unsymmetrical diaryl sulfones has been developed. The strategy takes advantage of the reaction of sulfonyl hydrazides with quinone imine ketals catalyzed
Intramolecular sulphonyl-amidomethylation. Part I. Cyclization of benzylsulphonamides
作者:Orfeo O. Orazi、Renée A. Corral、Rodolfo Bravo
DOI:10.1002/jhet.5570230620
日期:1986.11
strong acid media is a synthetically useful route to 3,4-dihydro-1H-2,3-benzothiazine2,2-dioxides III. With insufficient acid strength or reaction time, kinetic products IV and VI are obtained; the latter compounds can be converted into the thermodynamic products III under stronger conditions. The reactions proceed via imine VII or iminium VIII compounds as common intermediates.
在强酸介质中苄基磺酰胺与醛的环化是合成3,4-二氢-1 H -2,3-苯并噻嗪2,2-二氧化物III的合成途径。在不足的酸强度或反应时间的情况下,获得了动力学产物IV和VI。后者的化合物可以在更强的条件下转化为热力学产物III。反应通过亚胺VII或亚胺VIII化合物作为常见中间体进行。
Ligand-Free Palladium(II)-Catalyzed <i>ortho</i>
-C-H Chalcogenations of <i>N</i>
-Arylsulfonamide via Weak Coordination
作者:Linghui Gu、Xinyue Fang、Zhengyun Weng、Yupin Song、Wenbo Ma
DOI:10.1002/ejoc.201900050
日期:2019.2.28
The first palladium(II)‐catalyzed direct ortho‐C(sp2)–H chalcogenations of N‐arylsulfonamide via weak coordination have been achieved. This strategy features ligand/additive‐free conditions, broad substrate scope with excellent functional group tolerance and a high position selectivity.