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
Rhenium- and manganese-catalyzedreactions between beta-keto esters and acetylenes, followed by treatment with tetrabutylammonium fluoride, gave 2-pyranone derivatives regioselectively.
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.
Ruthenium(II)-Catalyzed Alkene C–H Bond Functionalization on Cinnamic Acids: A Facile Synthesis of Versatile α-Pyrones
作者:Rashmi Prakash、Kommuri Shekarrao、Sanjib Gogoi
DOI:10.1021/acs.orglett.5b02631
日期:2015.11.6
An inexpensive ruthenium(1) complex enabled oxidative annulation of alkynes by using cinnamic acid derivatives to provide diversely decorated multisubstituted alpha-pyrones.
Rhenium-Catalyzed Synthesis of Multisubstituted Aromatic Compounds via C−C Single-Bond Cleavage
A reaction between a beta-keto ester and an acetylene in the presence of a rhenium complex, [ReBr(CO)(3)(thf)](2), as a catalyst, provided a 2-pyranone derivative in excellent yield via retro-aldol reaction (C-C single bond cleavage). By adding an acetylene-bearing ester group(s) after the formation of 2-pyranones, an aromatization reaction proceeded and multisubstituted aromatic compounds were obtained in good to excellent yields.