Chiral Naphthyl-C2-Indole as Scaffold for Phosphine Organocatalysis: Application in Asymmetric Formal [4 + 2] Cycloaddition Reactions
作者:Tingting He、Lei Peng、Shan Li、Fangli Hu、Chuandong Xie、Shengli Huang、Shiqi Jia、Wenling Qin、Hailong Yan
DOI:10.1021/acs.orglett.0c02519
日期:2020.9.4
naphthyl-C2-indole bifunctional phosphine organocatalyst in stereoselective formal [4 + 2] cycloadditionreactions were reported. The chiral naphthyl-C2-indole skeleton was introduced to bifunctional phosphine organocatalysis for the first time, and excellent stereocontrol was achieved in two types of formal [4 + 2] cycloadditionreactions. With the optimal catalyst, a series of chiral spirooxindole and hydrodibenzofuran
Multicomponent Reaction to Construct Spirocyclic Oxindoles with a Michael (Triple Michael)/Cyclization Cascade Sequence as the Key Step
作者:Jian Li、Ning Wang、Chunju Li、Xueshun Jia
DOI:10.1002/chem.201104071
日期:2012.7.27
new strategy to access highly unusual tricyclic oxindoles. From a synthetic point of view, this protocol is very interesting considering the high level of complexity reached in one step. The mechanism is thought to proceed by a tripleMichael/cyclization process by using allenoate as a three carbon atom component (3 C). Furthermore, multicomponentreaction with γ‐substituted allenoate also results in
Bi(OTf)3-catalyzed sp3 C–H functionalization of 2-alkyl azaarenes to isatylidene malononitriles has been achieved to give oxindoles containing an all-carbon quaternary center.
Phosphine-Catalyzed Asymmetric Formal [4+2] Tandem Cyclization of Activated Dienes with Isatylidenemalononitriles: Enantioselective Synthesis of Multistereogenic Spirocyclic Oxindoles
作者:Fang-Le Hu、Yin Wei、Min Shi
DOI:10.1002/adsc.201301070
日期:2014.3.10
enantioselective formal [4+2] tandem cyclizations between isatylidenemalononitriles and activated dienes catalyzed by bifunctional chiral phosphine catalysts have been developed, yielding multistereogenic spirocyclicoxindoles in high yields and excellent optical purity. This reaction is accomplished via a tandem Rauhut–Currier/Michael/Rauhut–Currier reactionsequence.
已开发出双功能手性膦催化剂催化的异亚乙基丙二腈和活化的二烯之间的第一个高度对映选择性的正式[4 + 2]串联环化反应,可高收率和出色的光学纯度产生多立体异构螺环式吲哚。该反应是通过串联的Rauhut-Currier / Michael / Rauhut-Currier反应序列完成的。
Metal-Free Dehydrogenative Diels-Alder Reactions of 2-Methyl-3-Alkylindoles with Dienophiles: Rapid Access to Tetrahydrocarbazoles, Carbazoles, and Heteroacenes
作者:Liejin Zhou、Bing Xu、Junliang Zhang
DOI:10.1002/anie.201503549
日期:2015.7.27
ortho‐quinodimethanes (oQDMs) from 2‐methyl‐3‐alkylmethylindoles by either a metal‐free DDQ‐ or BQ‐mediated dehydrogenative process was developed. These oQDMs were trapped by electron‐deficient dienophiles to provide a facile approach to synthetically valuable tetrahydrocarbazoles, carbazoles, and hetereoacenes. The salient features of this transformation include direct C(sp3)H bond functionalizations