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。
Palladium-Catalyzed Cross-Coupling of Unactivated Aryl Sulfides with Arylzinc Reagents under Mild Conditions
Cross‐coupling of general aryl alkyl sulfides with arylzincreagents proceeds smoothly, even at room temperature or below, with a palladium–N‐heterocyclic carbene (NHC) catalyst. When combined with reactions that are unique to organosulfurs, that is, the SNAr sulfanylation or Pummerer reaction, the cross‐coupling offers interesting transformations that are otherwise difficult to achieve. An alkylsulfanyl
一般的芳基烷基硫化物与芳基锌试剂的交叉偶联,即使在室温或低于室温下,使用钯-N-杂环卡宾(NHC)催化剂也能顺利进行。当与有机硫特有的反应(即S N Ar磺酰化或Pummerer反应)结合使用时,交叉偶联可提供有趣的转化,而这些转化很难实现。烷基硫烷基优先被转化,而甲苯磺酰氧基和氯完好无损,这扩大了正交交叉偶联的种类。
Synthese regiospecifique d'allenes terminaux a partir de propargyltrimethylsilanes simples ou fonctionnels
作者:J. Pornet、D. Damour、L. Miginiac
DOI:10.1016/s0022-328x(00)99606-2
日期:1987.1
Protodesilylation of varied propargyltrimethylsilanes, using boron trifluorideacetic acid as reagent, give regiospecifically terminal allenes with very good yields. Yet, particular ω-functional propargyltrimethylsilanes may lead to vinylsilanes resulting from a ring-closing cyclisation reaction.
Synthesis of C2 Substituted Benzothiophenes via an Interrupted Pummerer/[3,3]-Sigmatropic/1,2-Migration Cascade of Benzothiophene <i>S</i>
-Oxides
作者:Zhen He、Harry J. Shrives、José A. Fernández-Salas、Alberto Abengózar、Jessica Neufeld、Kevin Yang、Alexander P. Pulis、David J. Procter
DOI:10.1002/anie.201801982
日期:2018.5.14
Functionalized benzothiophenes are important scaffolds found in molecules with wide ranging biological activity and in organic materials. We describe an efficient, metal‐free synthesis of C2 arylated, allylated, and propargylated benzothiophenes. The reaction utilizes synthetically unexplored yet readily accessible benzothiophene S‐oxides and phenols, allyl‐, or propargyl silanes in a unique cascade
A combination of a palladium–NHC catalyst and potassium hexamethyldisilazide enables the amination of aryl sulfides with anilines to afford a wide variety of diarylamines. The reaction conditions are versatile enough for the reaction of even bulky ortho‐substituted aryl sulfides. This amination can be applied to the modular synthesis of N‐aryl carbazoles from the corresponding ortho‐bromothioanisoles