Design, Preparation, X-ray Crystal Structure, and Reactivity of <i>o</i>-Alkoxyphenyliodonium Bis(methoxycarbonyl)methanide, a Highly Soluble Carbene Precursor
作者:Chenjie Zhu、Akira Yoshimura、Lei Ji、Yunyang Wei、Victor N. Nemykin、Viktor V. Zhdankin
DOI:10.1021/ol301268j
日期:2012.6.15
The preparation, X-ray structure, and reactivity of new, highly soluble, and reactive iodonium ylides derived from malonate methyl ester and bearing an ortho substituent on the phenyl ring are reported. These new reagents show higher reactivity than common phenyliodonium ylides in the Rh-catalyzed cyclopropanation, C–H insertion, and transylidation reactions under homogeneous conditions.
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.
Reduction of semipolar sulphur linkages with carbodithioic acids and addition of carbodithioic acids to olefins
作者:S. Oae、T. Yagihara、T. Okabe
DOI:10.1016/s0040-4020(01)93661-0
日期:1972.1
Carbodithioic acids react with trivalent sulphur compounds bearing semipolarlinkages (sulphoxides, sulphonium ylides and sulphilimines), to give the corresponding sulphides and add to olefins to afford dithioesters. The orientation of olefin addition is controlled by the olefin nature. Michael type addition takes place with olefins bearing an electron-withdrawing group α to the double bond while Markownikoff
Gold-Catalyzed Intermolecular Synthesis of Alkylidenecyclopropanes through Catalytic Allene Activation
作者:Juliette Sabbatani、Xueliang Huang、Luís F. Veiros、Nuno Maulide
DOI:10.1002/chem.201402935
日期:2014.8.18
A stereoselective gold(I)‐catalyzed intermolecular cyclopropanation of allenamides with stabilized sulfonium ylides is reported. This transformation enables the direct synthesis of diacceptor alkylidenecyclopropanes and proceeds under very mild conditions throughalleneactivation.