Synthesis of Donor-Acceptor Alkynylcyclopropanes by Diastereoselective Cyclopropanation of Electron-Deficient Alkenes with Alkoxyalkynyl Fischer Carbene Complexes
作者:José Barluenga、Manuel A. Fernández-Rodríguez、Patricia García-García、Enrique Aguilar、Isabel Merino
DOI:10.1002/chem.200500918
日期:2006.1
The reaction of electron-deficient alkenes with alkoxyalkynyl Fischercarbenecomplexes (FCCs) represents a straightforward route to a new type of captodative (donor-acceptor) alkynylcyclopropanes, which have been prepared in moderate to high yields and in a diastereoselective manner. Some studies regarding the employment of additives to facilitate the recovery of the metal moiety after the reaction
Low temperature carbene transfer from alkoxychromium(0) (Fischer) carbene complexes
作者:Miguel A Sierra、Juan C del Amo、Marı́a J Mancheño、Mar Gómez-Gallego
DOI:10.1016/s0040-4039(01)01082-6
日期:2001.8
Irradiation at lowtemperatures (0°C) of alkyl-, aryl- and styryl alkoxychromium(0)carbene complexes in the presence of methyl acrylate produces a mixture of diastereomeric cyclopropanes and C–H insertion derivatives. The ratio cyclopropane/C–H insertion product is independent of the reaction conditions, while the cyclopropane cis:trans ratio strongly depends on the solvent, the selectivity increasing