Catalytic Ring-Opening of Cyclic Alcohols Enabled by PCET Activation of Strong O–H Bonds
作者:Hatice G. Yayla、Huaiju Wang、Kyle T. Tarantino、Hudson S. Orbe、Robert R. Knowles
DOI:10.1021/jacs.6b06517
日期:2016.8.31
the redox-neutral isomerization of cyclic alcohols to linear ketones via C-C bond scission. Mechanistic studies demonstrate that key alkoxy radical intermediates in this reaction are generated via the direct homolytic activation of alcohol O-H bonds in an unusual intramolecular PCET process, wherein the electron travels to a proximal radical cation in concert with proton transfer to a weak Brønsted base
我们报告了一种新的光催化协议,用于通过 CC 键断裂将环醇氧化还原中性异构化为线性酮。机理研究表明,该反应中的关键烷氧基自由基中间体是通过在不寻常的分子内 PCET 过程中通过醇 OH 键的直接均裂活化而产生的,其中电子传播到邻近的自由基阳离子,同时质子转移到弱的布朗斯台德碱。显示有效的键强度考虑因素可以准确预测使用给定氧化剂/碱基对生成烷氧基自由基的可行性。
Nucleophilic<i>ortho</i>-Propargylation of Aryl Sulfoxides: An Interrupted Pummerer/Allenyl Thio-Claisen Rearrangement Sequence
作者:Andrew J. Eberhart、David J. Procter
DOI:10.1002/anie.201300223
日期:2013.4.2
A new direction: The nucleophilic ortho‐propargylation of aryl sulfoxides exploits intermolecular delivery of the nucleophile to sulfur followed by an intramolecular relay to carbon (see scheme). The simple, metal‐free procedure is general, regiospecific with regard to the propargyl nucleophile, and completely selective for products of ortho‐propargylation over allenylation.
A method was developed for the synthesis of 2-acylbenzo[b]thiophenes via a copper-catalyzed sulfuration of 3-(2-iodophenyl)-1-arylpropan-1-ones with K2S.
Sulfoxide-Directed Metal-Free<i>ortho</i>-Propargylation of Aromatics and Heteroaromatics
作者:Andrew J. Eberhart、Harry J. Shrives、Estela Álvarez、Amandine Carrër、Yuntong Zhang、David J. Procter
DOI:10.1002/chem.201406424
日期:2015.5.11
exploits intermolecular delivery of a propargyl nucleophile to sulfur followed by an intramolecular relay to carbon. The operationally simple cross‐coupling procedure is general, regiospecific with regard to the propargyl nucleophile, and shows complete selectivity for products of ortho‐propargylation over allenylation. The use of secondary propargyl silanes allows metal‐free ortho‐coupling to form carbon–carbon
作者:Hongyi Li、Chang Yin、Sien Liu、Hua Tu、Ping Lin、Jing Chen、Weiping Su
DOI:10.1039/d2sc05370e
日期:——
The dehydrogenation-triggered multiple C(sp3)–H functionalizations at remote positions γ, δ or ε, ζ to carbonyl groups of aliphatic ketones with aryl/alkenyl carboxylic acids as coupling partners have been achieved using a bimetallic Cu–Pd catalyst system. This reaction allows access to alkenylated isocoumarins and their derivatives in generally good yields with high functional group tolerance. The