检查了甲氧基-芳基乙炔砜与各种碳负离子亲核试剂反应生成三种类型的产物。因此,(i)亲核试剂(MeLi·LiBr,乙烯基MgBr,LiCH 2 CN)显示出α加成,但是,(ii)Li– CC C–TMS提供了β加成(共轭加成)产物。通过在高温下存在邻甲氧基,可以增强通过α-加成/异构化/反式消除的(iii)置换反应。质子溶剂中的杂原子亲核试剂(氮,氧或硫原子)仅提供了所报道的缀合物加成产物。
Abstract An efficient decarboxylative sulfonylation of arylacetylenic acids with sodium arylsulfinates has been achieved by an electro-oxidative strategy. This novel protocol offers a simple, efficient, and green route to a series of arylacetylenic sulfones in moderate yields under metal-free and external oxidant-free conditions. Graphical Abstract
Visible‐Light‐Induced Three‐Component Intermolecular Trifluoromethyl‐Alkenylation Reactions of Unactivated Alkenes
作者:Yuan‐Qiang Guo、Kaihua Wang、Ruiguo Wang、Hongjian Song、Yuxiu Liu、Qingmin Wang
DOI:10.1002/adsc.202001434
日期:2021.3.16
visible‐light‐induced three‐component intermolecular trifluoromethyl‐alkenylation reactions of unactivated alkenes. The protocol has good functional group tolerance and a broad substrate scope. Using this protocol, we not only introduced a trifluoromethyl group into alkenes but also converted unactivated alkenes to styrene‐based activated alkenes, in addition to accomplishing late‐stage functionalization of pharmaceutical
radical‐mediated C−H alkynylation reaction of inactivated alkanes was described. The reaction features mild operation condition and wide substrate scope, and affords the corresponding products in moderate to good yields. Notably, The presence of 4‐cyanopyride N‐oxide was key to the success of the reaction. Cyclohexane are more easily to be functionalized in this reaction than toluene, which could be rationally
synthesis of a vast variety of heteroatom‐containing cyclobutene‐triflones [bis(trifluoromethylsulfonyl)cyclobutenes] and cyclobutenones has been developed starting from heteroatom‐substituted alkynes and a pyridinium salt (a latent Tf2C=CH2 source). This powerful methodology, involving cyclization reactions, allows for the selective preparation of oxygen‐, nitrogen‐, bromine‐, chlorine‐, iodine‐, sulfur‐
从杂原子取代的炔烃和吡啶鎓盐(潜在的Tf 2 C = CH 2来源)开始,开发了可控制的无金属合成各种杂原子的环丁烯-triflones [双(三氟甲基磺酰基)环丁烯]和环丁烯酮。。这种强大的方法涉及环化反应,可以选择性地制备氧,氮,溴,氯,碘,硫,硒,碲,磷和硅官能化的环丁烯衍生物。
Electrochemical Sulfonylation of Alkynes with Sulfonyl Hydrazides: A Metal‐ and Oxidant‐Free Protocol for the Synthesis of Alkynyl Sulfones
Herein, an electrochemical oxidative cross‐coupling reaction between terminal alkynes and sulfonylhydrazides has been developed. Tetrabutylammonium iodide is used as the electrolyte and redox medium. The significant advantages of this method are high atom efficiency, functional group tolerance, and transition metal‐ and oxidant‐free conditions. Most of the compounds exhibit good inhibitory activity