Carbodiphosphoranes [C(PR3)2] are divalentcarbon(0) derivatives which can be used as ligands to form either MC(PR3)2 or (M)2 C(PR3)2 species. They were computationally predicted to be even stronger electron donors than N-heterocyclic carbenes. We have introduced hexaphenylcarbodiphosphorane [C(PPh3)2] for the first time in gold catalysis in order to validate this prediction by experimentation. Its
Gold(I)-Catalyzed Intermolecular Addition of Carbon Nucleophiles to 1,5- and 1,6-Enynes
作者:Catelijne H. M. Amijs、Verónica López-Carrillo、Mihai Raducan、Patricia Pérez-Galán、Catalina Ferrer、Antonio M. Echavarren
DOI:10.1021/jo8014769
日期:2008.10.3
Gold(I)-catalyzed addition of carbon nucleophiles to 1,6-enynes gives two different type of products by reaction at the cyclopropane or at the carbene carbons of the intermediate cyclopropyl gold carbenes. The 5-exo-dig cyclization is followed by most 1,6-enynes, although those bearing internal alkynes and alkenes react by the 6-endo-dig pathway. The cyclopropane versus carbene site-selectivity can
An Atom-Economic Synthesis of Bicyclo[3.1.0]hexanes by Rhodium N-Heterocyclic Carbene-Catalyzed Diastereoselective Tandem Hetero-[5 + 2] Cycloaddition/Claisen Rearrangement Reaction of Vinylic Oxiranes with Alkynes
作者:Jian-Jun Feng、Junliang Zhang
DOI:10.1021/ja2014604
日期:2011.5.18
The first synthetic application of a vinylic oxirane as a heteroatom-containing five-atom component in transition-metal-catalyzed cycloadditionreactions is reported. A new, efficient, diastereoselective tandem intramolecular hetero-[5+2] cycloaddition/Claisen rearrangement of vinylic oxirane-alkyne substrates that uses a rhodium NHC complex and provides strategically novel, atom-economic, regiospecific
<i>cis</i>-Selective Single-Cleavage Skeletal Rearrangement of 1,6-Enynes Reveals the Multifaceted Character of the Intermediates in Metal-Catalyzed Cycloisomerizations
作者:Eloísa Jiménez-Núñez、Christelle K. Claverie、Christophe Bour、Diego J. Cárdenas、Antonio M. Echavarren