Copper-Catalyzed Enantioselective Intramolecular Conjugate Addition/Trapping Reactions: Synthesis of Cyclic Compounds with Multichiral Centers
作者:Kangying Li、Alexandre Alexakis
DOI:10.1002/chem.200601327
日期:2007.4.27
The Cu-catalyzed enantioselective conjugate addition of dialkylzinc to bis-alpha,beta-unsaturated carbonyl compounds followed by the intramolecular trapping of the zinc enolate in the presence of chiral phosphoramidite ligands was investigated. Cyclic and heterocyclic compounds with multichiral centers were formed as a mixture of two diastereomers with excellent diastereoselectivities (up to 99:1)
Tandem Michael/Michael reactions mediated by phosphines or aryl thiolates
作者:Paul M Brown、Nina Käppel、Patrick J Murphy
DOI:10.1016/s0040-4039(02)02142-1
日期:2002.11
Tri-n-Butyl phosphine was found to effect tandem Michael/Michael cyclisations leading to the formation of cyclopentenes and cyclohexenes in good yields, whilst p-TolSH in conjunction with a catalytic amount of p-TolSNa effected cyclisation to the corresponding cyclopentanes and cyclohexanes. (C) 2002 Published by Elsevier Science Ltd.
Copper catalyzed tandem asymmetric conjugate addition–cyclization reaction in the presence of chiral phosphoramidite ligands
作者:Kangying Li、Alexandre Alexakis
DOI:10.1016/j.tetlet.2005.09.065
日期:2005.11
Copper-catalyzed intramolecular conjugate addition-cyclization in the presence of chiral phosphoramidite ligands was described. Cyclic products with multiple chiral centers were obtained with up to 93:7 diastereomeric ratio and 94% ee. (c) 2005 Elsevier Ltd. All rights reserved.
Concise synthesis of oxacyclic compounds using highly discriminative two-way transformations of α,β-unsaturated esters in the presence of enones
Highly discriminative transformation of α,β-unsaturated esters in the presence of enones using two types of phosphonium salts, and their application to the synthesis of oxacyclic compounds in six steps in one pot have been achieved.