Gold-Catalyzed Synthesis of Furans and Furanones from Sulfur Ylides
作者:Xueliang Huang、Bo Peng、Marco Luparia、Luis F. R. Gomes、Luís F. Veiros、Nuno Maulide
DOI:10.1002/anie.201203637
日期:2012.8.27
A golden switch: Doubly stabilized sulfonium ylides can be coupled with alkynes in a gold‐catalyzed synthesis of heterocycles. This method hinges on a switch in the reactivity of the sulfur ylide resulting from the simple modification of the electron‐withdrawing moieties and leads to either furans or furanones bearing a quaternary center (see scheme).
The development of a direct ylide transfer to carbonyl derivatives and of a sulfoxide-mediated arylation is presented from a unified perspective. Mechanistic studies (including density functional calculations) support a common reaction pathway and showcase how subtle changes in reactant properties can lead to disparate and seemingly unrelated reaction outcomes.
A Direct Ylide Transfer to Carbonyl Derivatives and Heteroaromatic Compounds
作者:Xueliang Huang、Richard Goddard、Nuno Maulide
DOI:10.1002/anie.201002919
日期:2010.11.15
Power transfer: The title reaction proceeds under mild conditions (room temperature, short reaction times) and directly affords sulfoniumylidesfrom active methylene compounds and heteroaromatics in a single step and in high yields. A detailed comparative structural analysis of a variety of ylides is presented and the implications of structure on the reactivity of these compounds are discussed.
Stereoselective intramolecular cyclopropanation through catalytic olefin activation
作者:Xueliang Huang、Sebastian Klimczyk、Luís F. Veiros、Nuno Maulide
DOI:10.1039/c2sc21914j
日期:——
A novel stereoselective and convergent catalytic method for the cyclopropanation of electron-neutral and -rich olefins by sulfonium ylides is reported which unusually proceeds through olefin activation rather than by metal carbene formation.
Stereoselective Gold(I) Domino Catalysis of Allylic Isomerization and Olefin Cyclopropanation: Mechanistic Studies
作者:Sebastian Klimczyk、Xueliang Huang、Hanspeter Kählig、Luís F. Veiros、Nuno Maulide
DOI:10.1021/acs.joc.5b00666
日期:2015.6.5
Gold(I) catalysis of olefin activation is still a rare feature in the repertoire of that metal. Mechanistic studies on the gold(I)-catalyzedcyclopropanation of allyl-substituted sulfonium ylides, including kinetic analysis as well as detailed computational studies, reveal that the reaction proceeds through activation of the alkene moiety. Furthermore, a novel competitive allylic isomerization pathway