Diastereoselective cyclopropanation of cyclic enones with methyl dichloroacetate anion
作者:Ana Escribano、Concepción Pedregal、Rosario González、Alejandro Fernández、Keith Burton、Gregory A Stephenson
DOI:10.1016/s0040-4020(01)00949-8
日期:2001.11
The reaction of alpha,beta -unsaturated cyclic ketones with methyl dichloroacetate anion in the presence of DBU leads to the corresponding bicyclic chlorocyclopropanes in a highly diastereoselective fashion. In the cases of 2-cyclopentenone and 2-cyclohexenone the reaction affords exclusively the endo-Cl isomer. (C) 2001 Elsevier Science Ltd. All rights reserved.
Ring Opening of Bicyclo[3.1.0]hexan‐2‐ones: A Versatile Synthetic Platform for the Construction of Substituted Benzoates
Described is the development of a highly efficient 2π disrotatory ring‐opening aromatization sequence using bicyclo[3.1.0]hexan‐2‐ones. This unprecedented transformation efficiently proceeds under thermal conditions and allows facile construction of uniquely substituted and polyfunctionalized benzoates. In the presence of either amines or alcohols formation of substituted anilines or ethers, respectively,
Formation of polysubstituted chlorocyclopropanes from electrophilic olefins and activated trichloromethyl compounds
作者:Sylvain Oudeyer、Eric Léonel、Jean Paul Paugam、Christine Sulpice-Gaillet、Jean-Yves Nédélec
DOI:10.1016/j.tet.2005.11.001
日期:2006.2
Chlorocyclopropanes and bicyclic chlorocyclopropanes are prepared in non basic conditions by electroreductive or Mg-promoted Barbier activation of PhCCl3 or Cl3CCO2Me in the presence of acyclic or cyclic α,β-unsaturated carbonyl compounds.