Catalyst-free room-temperature decarboxylative tri- or tetrafunctionalization of alkynyl carboxylic acids with <i>N</i>-fluorobenzenesulfonimide (NFSI) and diselenides
作者:Ying-chun Wang、Li-qiu Liu、Guang-mang Wang、Hui Ouyang、You-ji Li
DOI:10.1039/c7gc03267f
日期:——
The combination of N-fluorobenzenesulfonimide (NFSI) with diselenides allowed the rapid decarboxylative tri- or tetrafunctionalization of alkynyl carboxylic acids under catalyst-free room-temperature conditions. This reaction offers an novel and facile route to polyseleno-substituted enamines.
Boronic Acid Catalysis for Mild and Selective [3+2] Dipolar Cycloadditions to Unsaturated Carboxylic Acids
作者:Hongchao Zheng、Robert McDonald、Dennis G. Hall
DOI:10.1002/chem.200903484
日期:2010.5.10
activation of unsaturated carboxylic acids is applied in several classic dipolar [3+2] cycloadditions involving azides, nitrile oxides, and nitrones as partners. These cycloadditions can be used to produce pharmaceutically interesting, small heterocyclic products, such as triazoles, isoxazoles, and isoxazolidines. These cycloadducts are formed directly and include a free carboxylic acid functionality that can
Syntheses of α-Pyrones Using Gold-Catalyzed Coupling Reactions
作者:Tuoping Luo、Mingji Dai、Shao-Liang Zheng、Stuart L. Schreiber
DOI:10.1021/ol200794w
日期:2011.6.3
Sequential alkyne activation of terminal alkynes and propiolic acids by gold(I) catalysts yields compounds having α-pyrone skeletons. Novel cascade reactions involving propiolic acids are reported that give rise to α-pyrones with different substitution patterns.
Palladium(II) Acetate-Catalyzed Dual C-H Functionalization and C-C Bond Formation: A Domino Reaction for the Synthesis of Functionalized (<i>E</i>)-Bisindole-2-ones from Diarylbut-2-ynediamides
A domino reaction of palladium(II)‐catalyzed dual C–H functionalization with subsequent intramolecular annulation is presented. This method provides a convenient synthesis of a range of symmetrical and unsymmetrical biologically important (E)‐bisindole‐2‐ones under extremely mild reaction conditions – room temperature, green oxidant and no additive. The reaction mechanism is elucidated in light of
A Rare Alder‐ene Cycloisomerization of 1,6‐Allenynes
作者:Liam M. Joyce、Melanie A. Drew、Andrew J. Tague、Thanaphat Thaima、Ali Gouranourimi、Alireza Ariafard、Stephen G. Pyne、Christopher J. T. Hyland
DOI:10.1002/chem.202104022
日期:2022.2.24
Alder-ene reaction: Thermally induced intramolecular Alder-ene reactions of 1,6-allenynes gives α-methylene-γ-lactams via a mechanism distinct from previous [2+2] cycloisomerization manifolds of related skeletons. The mechanism involves an unusual transfer of the allene-hydrogen and is supported by computational and deuterium labelling studies. The reaction is favoured by the electron-deficient nature