Exploration of Biaryl Carboxylic Acids as Proton Shuttles for the Selective Functionalization of Indole C–H Bonds
摘要:
A survey of diversely substituted 2-arylbenzoic acids were synthesized and tested for use as proton shuttle in the direct arylation of indoles with bromobenzenes. It was found that 3-ethoxy-2-phenylbenzoic acid gives superior yield and selectivity for this class of substrates.
Exploration of Biaryl Carboxylic Acids as Proton Shuttles for the Selective Functionalization of Indole C–H Bonds
摘要:
A survey of diversely substituted 2-arylbenzoic acids were synthesized and tested for use as proton shuttle in the direct arylation of indoles with bromobenzenes. It was found that 3-ethoxy-2-phenylbenzoic acid gives superior yield and selectivity for this class of substrates.
Compounds and Methods for Catalytic Directed ortho Substitution of Aromatic Amides and Esters
申请人:Zhao Yigang
公开号:US20120302752A1
公开(公告)日:2012-11-29
Methods are described for efficient and regioselective reactions that are Ru-catalyzed and either (i) amide-directed C—H, C—N, C—O activation/C—C bond forming reactions, (ii) ester-directed C—O and C—N activation/C—C bond forming reactions, or (iii) amide-directed C—O activation/hydrodemethoxylation reactions. All of these reactions of directed C—H, C—N, C—O activation/coupling reactions establish a catalytic base-free DoM-cross coupling process at non-cryogenic temperature. High regioselectivity, yields, operational simplicity, low cost, and convenient scale-up make these reactions suitable for industrial applications. Many previously unknown amide-substituted or ester-substituted aryl and heteroaryl compounds are presented with synthetic details also provided.
Preparation and Palladium-Catalyzed Cross-Coupling of Aryl Triethylammonium Bis(catechol) Silicates with Aryl Triflates
作者:W. Michael Seganish、Philip DeShong
DOI:10.1021/jo035309q
日期:2004.2.1
Pentavalent aryl and heteroaryl bis(catechol) silicates undergo palladium-catalyzedcross-coupling with aryl and heteroaryl triflates in the presence of a fluoride source in excellent yields. These solid, air-stable bis(catechol) silicates are prepared from a high-yielding displacement reaction between catechol and an aryl siloxane in the presence of an amine base. The cross-couplingreaction is tolerant
Regio- and Chemoselective Kumada–Tamao–Corriu Reaction of Aryl Alkyl Ethers Catalyzed by Chromium Under Mild Conditions
作者:Xuefeng Cong、Huarong Tang、Xiaoming Zeng
DOI:10.1021/jacs.5b08621
日期:2015.11.18
the cross-coupling reactions with arylethers via C-O bond activation have attracted broad interest. However, the functionalizations of C-O bonds are mainly limited to nickel catalysis, and selectivity has long been a prominent challenge when several C-O bonds are present in the one molecule. We report here the first chromium-catalyzed selective cross-coupling reactions of arylethers with Grignard reagents
作为一种环境友好的合成工具,通过 CO 键活化与芳基醚的交叉偶联反应引起了广泛的兴趣。然而,CO 键的功能化主要限于镍催化,当一个分子中存在多个 CO 键时,选择性一直是一个突出的挑战。我们在这里报告了第一个铬催化的芳基醚与格氏试剂通过 CO(烷基)键断裂的选择性交叉偶联反应。在室温下使用简单、廉价的铬 (II) 预催化剂结合亚氨基助剂实现了多种转化。它为高效和选择性地构建官能化芳香醛提供了新途径。
Chromium-Catalyzed, Regioselective Cross-Coupling of C–O Bonds by Using Organic Bromides as Reactants
作者:Meiming Luo、Xiaoming Zeng、Jinghua Tang
DOI:10.1055/s-0036-1588568
日期:2017.12
cross-coupling of C–O bonds with widely accessible organic bromides as reactants for the preparation of ortho-arylated or -alkylated aromaticaldehydes at room temperature. The use of metallic magnesium is essential for the reaction to occur, giving it an advantage over previous reactions involving Grignard reagents that have to be prepared separately from organic halides before the coupling.