作者:Qi-Liang Yang、Yi-Kang Xing、Xiang-Yang Wang、Hong-Xing Ma、Xin-Jun Weng、Xiang Yang、Hai-Ming Guo、Tian-Sheng Mei
DOI:10.1021/jacs.9b11915
日期:2019.12.4
Synergistic use of electrochemistry and organometallic catalysis has emerged as a powerful tool for site-selective C-H functionalization, yet this type of transformation has thus far mainly been limited to arene C-H functionaliza-tion. Herein, we report the development of electrochemi-cal vinylic C-H functionalization of acrylic acids with al-kynes. In this reaction an iridium catalyst enables C-H/O-H
Oxidative Annulation of Arenecarboxylic and Acrylic Acids with Alkynes under Ambient Conditions Catalyzed by an Electron-Deficient Rhodium(III) Complex
It has been established that an electron‐deficient CpE rhodium(III) complex catalyzes the oxidative [4+2] annulation of substituted arenecarboxylic and acrylic acids with alkynes under ambient conditions (at RT–40 °C, under air) without using excess amounts of substrates to produce the corresponding substituted isocoumarins and α‐pyrones in high yields. Minor modification of reaction conditions depending
Synthesis of Functionalized α-Pyrone and Butenolide Derivatives by Rhodium-Catalyzed Oxidative Coupling of Substituted Acrylic Acids with Alkynes and Alkenes
The straightforward and efficient synthesis of α-pyrone and butenolide derivatives has been achieved by the rhodium-catalyzedoxidativecoupling reactions of substituted acrylic acids with alkynes and alkenes, respectively. Some α-pyrones obtained exhibit solid-state fluorescence.
Rhodium(<scp>iii</scp>)-catalysed decarbonylative coupling of maleic anhydrides with alkynes
作者:Takanori Matsuda、Kentaro Suzuki
DOI:10.1039/c4ra06452f
日期:——
A formal [5 − 1 + 2] annulation for the preparation of substituted α-pyrones is reported. The reaction involves the decarbonylative coupling of substituted maleicanhydrides with internal alkynes in the presence of a rhodium(III) catalyst and a copper(II) salt, affording tri- and tetrasubstituted α-pyrones.
The dehydrogenative coupling of maleic acids with alkynes proceeds smoothly accompanied by decarboxylation under rhodium catalysis to produce variously substituted a-pyrone derivatives. The catalyst system is also applicable to the coupling with 1,3-diynes and alkenes.