indole‐based biaryls with bromoalkyl alkynes by using palladium/norbornene (Pd/NBE) cooperative catalysis. This reaction is realized through a sequence of Catellani‐type C−H alkylation, alkyneinsertion, and indole dearomatization, by forming twoC(sp2)−C(sp3) and one C(sp2)−C(sp2) bonds in a single chemical operation, thus providing a diverse range of pentacyclic molecules, containing a spiroindolenine fragment
Organocatalytic Asymmetric One-Step Desymmetrizing Dearomatization Reaction of Indoles: Development and Bioactivity Evaluation
作者:Lei Peng、Da Xu、Xiaohong Yang、Jiakun Tang、Xuli Feng、Shao-Lin Zhang、Hailong Yan
DOI:10.1002/anie.201811437
日期:2019.1.2
An organocatalytic one‐step desymmetrizing dearomatizationreaction of indoles with in situ formed vinylidene ortho‐quinonemethides is reported. A set of [6‐6‐5] and/or [5‐6‐5] fused indoline heterocycles were obtained in excellent yields with excellent diastereoselectivities (>20:1 d.r.) and enantioselectivities (up to 99 % ee). Moreover, some of the obtained products were screened against a panel
Synthesis of Fused Polycycles by 1,4-Palladium Migration Chemistry
作者:Qinhua Huang、Marino A. Campo、Tuanli Yao、Qingping Tian、Richard C. Larock
DOI:10.1021/jo048788h
日期:2004.11.1
Novel palladium migration/arylation methodology for the synthesis of complex fused polycycles has been developed, in which one or more sequential Pd-catalyzed intramolecular migration processes involving C-H activation are employed. The chemistry works best with electron-rich aromatics, which is in agreement with the idea that these palladium-catalyzed C-H activation reactions parallel electrophilic aromatic substitution.
Aryl to Aryl Palladium Migration in the Heck and Suzuki Coupling of <i>o</i>-Halobiaryls
作者:Marino A. Campo、Haiming Zhang、Tuanli Yao、Abdellatif Ibdah、Ryan D. McCulla、Qinhua Huang、Jian Zhao、William S. Jenks、Richard C. Larock
DOI:10.1021/ja069238z
日期:2007.5.1
A novel 1,4-palladium migration between the o- and o'-positions of biaryls has been observed in organopalladium intermediates derived from o-halobiaryls. The organopalladium intermediates generated by this migration have been trapped either by a Heck reaction employing ethyl acrylate or by Suzuki cross-coupling using arylboronic acids. This palladium migration can be activated or deactivated by choosing the appropriate reaction conditions. Chemical and computational evidence supports the presence of an equilibrium that correlates with the C-H acidity of the available arene positions.