Pd-Catalyzed Direct and Selective CH Functionalization: C3-Acetoxylation of Indoles
作者:Qiang Liu、Gang Li、Hong Yi、Pan Wu、Jie Liu、Aiwen Lei
DOI:10.1002/chem.201002547
日期:2011.2.18
one! A novel Pd‐catalyzed direct and selectiveC3‐acetoxylation of indole derivatives has been accomplished (see scheme). This selective CH activation reaction was implemented without the assistance of directing groups and took place undermildconditions. The kinetic study revealed that the reaction was zero‐order with respect to the oxidant and first‐order with respect to the indole derivatives.
Cobalt-Catalyzed Defluorosilylation of Aryl Fluorides via Grignard Reagent Formation
作者:Soobin Lim、Hyungdo Cho、Jongheon Jeong、Minjae Jang、Hyunseok Kim、Seung Hwan Cho、Eunsung Lee
DOI:10.1021/acs.orglett.0c02752
日期:2020.9.18
cheap electrophilic silicon source with magnesium. This method is compatible with various silicon sources and can be operated under aerobic conditions. Mechanistic studies support the in situ formation of a Grignard reagent, which is captured by the electrophilic silicon source.
Room-Temperature Palladium(II)-Catalyzed Direct 2-Arylation of Indoles with Tetraarylstannanes
作者:Yuxia Liu、Dong Xue、Chao Wang、Linjuan Huang
DOI:10.1055/s-0040-1707196
日期:2020.10
A palladium(II)-catalyzed direct 2-arylation of indoles by tetraarylstannanes with oxygen (balloon) as the oxidant at room temperature has been developed. Various tetraarylstannanes can be employed as aryl sources for 2-arylation of indoles in up to 89% yield, providing a practical and efficient catalytic protocol for accessing 2-arylindoles.
已开发出钯 (II) 催化的四芳基锡烷与氧(气球)作为氧化剂在室温下直接对吲哚进行 2-芳基化反应。各种四芳基锡烷可用作吲哚 2-芳基化的芳基来源,产率高达 89%,为获得 2-芳基吲哚提供了实用且有效的催化方案。
Chiral Macrocycle‐Enabled Counteranion Trapping for Boosting Highly Efficient and Enantioselective Catalysis
作者:Rui Ning、Hao Zhou、Shi‐Xin Nie、Yu‐Fei Ao、De‐Xian Wang、Qi‐Qiang Wang
DOI:10.1002/anie.202003673
日期:2020.6.26
manipulated for tuning the catalysis process. In parallel to well‐developed crown ether‐based cation‐binding catalysis, a macrocycle‐enabled counteranion trapping strategy is presented for boosting highly efficient and enantioselective catalysis. A set of bis‐diarylthiourea macrocycles containing two BINOL moieties were designed and synthesized. They possess a well‐confined chiral cavity and strong binding
Catalytic Electrophilic C−H Borylation Using NHC⋅Boranes and Iodine Forms C2-, not C3-, Borylated Indoles
作者:John S. McGough、Jessica Cid、Michael J. Ingleson
DOI:10.1002/chem.201702060
日期:2017.6.16
that this is due to C3 to C2 boron migration facilitated by the absence of exogenous Brønsted bases. Thus this C−H borylation methodology proceeds under sufficiently Brønsted acidic conditions to enable the thermodynamic C2‐borylated indole isomer to be formed instead of the C3 borylated‐isomer. This demonstrates that electrophilic C−H borylation can be used to access a wider range of borylated regioisomers
N-杂环卡宾硼烷活化(NHC⋅BH 3)由I 2使杂芳烃的形成与H的无金属催化C-H硼化2作为副产物的方法,它使用仅长凳稳定前体。使用NHC⋅BH吲哚的硼化3 / I 2与其他催化亲电CH硼化方法相比,仅能生产C2硼化的吲哚。机理研究表明,这是由于缺乏外源布朗斯台德碱促进了C3向C2硼的迁移。因此,这种CH硼化方法在足够的布朗斯台德酸性条件下进行,以形成热力学C2硼化的吲哚异构体,而不是C3硼化的异构体。这表明亲电CH硼化可以用于比迄今为止报道的更广泛的硼化区域异构体。