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.
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
Access to Benzo[<i>a</i>]carbazoles and Indeno[1,2-<i>c</i>]quinolines by a Gold(I)-Catalyzed Tunable Domino Cyclization of Difunctional 1,2-Diphenylethynes
The cyclization order of the difunctional 1,2-diphenylethynes was precisely tuned under the catalysis of gold by changing the nitrogen substitution of the substrates, leading to the facile preparation of benzo[a]carbazole and indeno[1,2-c]quinolinederivatives. The mechanisms of these domino cyclizations were probed by control experiments, and an insight into the selectivity of the cyclization was
通过改变底物的氮取代,在金的催化下精确调节了双官能1,2-二苯乙炔的环化顺序,从而轻松制备了苯并[ a ]咔唑和茚并[1,2- c ]喹啉衍生物。通过控制实验探索了这些多米诺环化的机理,并通过密度泛函理论(DFT)计算获得了对环化选择性的深入了解。这项研究代表了访问苯并[ a ]咔唑和茚并[1,2- c ]喹啉的统一而通用的方法。
Gold-Catalyzed Cascade Cyclization of (Azido)ynamides: An Efficient Strategy for the Construction of Indoloquinolines
(Azido)ynamides were efficiently converted into indoloquinolines by the use of a gold catalyst. While ynamides bearing an allylsilane gave terminal alkenes, ynamides bearing a simple alkene gave cyclopropanes. This reaction proceeds through the formation of an alpha-amidino gold carbenoid.
An unprecedented copper-catalyzed tandem cross-coupling/[2 + 2] cycloaddition of 1,6-allenynes with diazo compounds was reported, chemo- and regioselectively providing 3-azabicyclo[5.2.0] frameworks in moderate to excellent yields under mild reactionconditions. Moreover, the products readily convert to highly functionalized quinolines via oxidative radical rearrangement.