Palladium-Catalyzed Zinc-Amide-Mediated CH Arylation of Fluoroarenes and Heteroarenes with Aryl Sulfides
作者:Shinya Otsuka、Hideki Yorimitsu、Atsuhiro Osuka
DOI:10.1002/chem.201502101
日期:2015.10.12
heteroarenes with aryl sulfides proceeds smoothly with the aid of a palladium–N‐heterocyclic carbene catalyst. A bulky zinc amide, TMPZnCl⋅LiCl, plays a key role as an effective base to generate the corresponding arylzinc species in situ. This arylation protocol is practically much easier to perform than our previous method, which necessitates preparation of the arylzincreagents in advance from the corresponding
Ç polyfluoroarenes和杂芳烃的与芳基硫化物ħ芳基化用钯- N-杂环卡宾催化剂的帮助下顺利进行。甲笨重锌酰胺,TMPZnCl ⋅的LiCl,起着以原位产生相应的芳基锌物种的有效碱关键作用。该芳基化方案实际上比我们以前的方法更容易执行,后者需要从相应的芳基卤化物预先制备芳基锌试剂。通过硫特异性反应(如S N Ar磺酰化反应和扩展的Pummerer反应)制备的芳基硫化物会经历这种直接芳基化,从而提供有趣的转化,而这些转化是传统的基于卤素的有机合成难以实现的。
Additive Pummerer reaction of heteroaromatic sulfilimines with carbon nucleophiles
作者:Albert Padwa、Shinji Nara、Qiu Wang
DOI:10.1016/j.tetlet.2005.11.026
日期:2006.1
The additive Pummerer reaction of several heteroaromatic sulfilimines has been investigated. The overall process involves the reaction of the sulfilimine with TFAA to produce a transient N-tosyl-N-trifluoroacetyl sulfonium ion. Nucleophilic attack at the adjacent vinyl carbon results in the ejection of the sulfonamide group and the resulting thionium, ion loses a proton to give the observed product. (c) 2005 Elsevier Ltd. All rights reserved.
Dichloroketene-Induced Cyclizations of Vinyl Sulfilimines: Application of the Method in the Synthesis of (±)-Desoxyeseroline
作者:Albert Padwa、Shinji Nara、Qiu Wang
DOI:10.1021/jo051550o
日期:2005.10.1
to yield thioalkyl-substituted γ-lactams. The overall process involves nucleophilic addition of the nitrogen atom of the sulfilimine onto the highly electrophilic dichloroketene to first generate a zwitterionic intermediate. A subsequent [3,3]-sigmatropicrearrangement is followed by intramolecular trapping of the Pummerer cation by the amido anion to furnish the observed γ-lactam product. Incorporation