Synthesis of Indole-Fused Polycyclics via Rhodium-Catalyzed Undirected C–H Activation/Alkene Insertion
作者:Songjin Guo、Rui Pan、Zhe Guan、Panpan Li、Libo Cai、Siwei Chen、Aijun Lin、Hequan Yao
DOI:10.1021/acs.orglett.9b02198
日期:2019.8.16
Rh(III)-catalyzed undirected C–H activation/alkeneinsertion to synthesize diversified indole-fused polycyclics has been developed. Intramolecular electrophilic cyclization generated a 3-indolyl rhodium species that went through an aryl-to-aryl 1,4-rhodium migration to realize the C–H activation. The subsequent [4 + 2] carboannulation or hydroarylation of alkenes could be achieved, respectively, by simply
unprecedented radical difluoromethylarylation reaction of alkynes has been developed by discovering a new difluoromethylation reagent, CF2HSO2NHNHBoc. This air-stable and solid reagent can be prepared in one step from commercially available reagents CF2HSO2Cl and NH2NHBoc. The CF2H radical, generated through ferrocene-mediated electrochemical oxidation, participates in an unexplored alkyne addition reaction
A dramatic enhancing effect of InBr3 was observed towards the oxidative Sonogashira cross-coupling reaction of 2-ethynylaniline with (E)-trimethyl(3,3,3-trifluoroprop-1-enyl)silane.
A novel highly efficient, environmentally benign Lewis acid‐catalyzed, and protection‐free protocol for the construction of valuable polycyclic products bearing a 1H‐pyrrolo[1,2‐a]indole scaffold is described, starting from readily available propargylic alcohols and 2‐ethynylanilines. The one‐pot transformation entails the cleavage of one C−O bond, and the construction of two C−N bonds and one C−C
描述了一种新型的高效,环境友好的路易斯酸催化且无保护的方案,用于构建带有1 H-吡咯并[1,2- a ]吲哚骨架的有价值的多环产物,从容易获得的炔丙醇和2开始乙炔基苯胺。一锅转换需要裂解一个C-O键,两个C-N键和一个C-C双键。这种独特的操作简单的方法是在温和条件下和空气中进行的,产生的水是唯一的副产物。它具有可伸缩性,并显示出良好的功能组兼容性和广泛的适用范围。
Copper-Catalyzed Trifluoromethylation/Cyclization of Alkynes for Synthesis of Dioxodibenzothiazepines
作者:Zi-Qi Zhang、Yi-Hao Xu、Jing-Cheng Dai、Yan Li、Jie Sheng、Xi-Sheng Wang
DOI:10.1021/acs.orglett.1c00344
日期:2021.3.19
A facile and efficient approach for the synthesis of the CF3-containing dioxodibenzothiazepines has been developed via copper-catalyzed trifluoromethylation/cyclization of alkynes utilizing a radical relay strategy. This method has demonstrated low catalyst loading, high regiocontrol, and broad scope under mild conditions. Good compatibility for the N-protecting group, gram-scale experiment, and further