Stereoselective Multicomponent Reactions Using Zincate Nucleophiles: β-Dicarbonyl Synthesis and Functionalization
作者:Stephen K. Murphy、Mingshuo Zeng、Seth B. Herzon
DOI:10.1021/acs.orglett.6b02320
日期:2016.10.7
A general strategy for conjugate addition-C-acylation that enables the synthesis of enantioenriched β-dicarbonyl compounds is described. A novel method for derivatizing these adducts by stereo- and site-selective zinc-catalyzed addition of alkyllithium reagents is also reported. These reactions can be performed in tandem to achieve an enantio- and diastereoselective four-component coupling. The in
Highly Enantioselective Catalytic Conjugate Addition and Tandem Conjugate Addition–Aldol Reactions of Organozinc Reagents
作者:Ben L. Feringa、Mauro Pineschi、Leggy A. Arnold、Rosalinde Imbos、André H. M. de Vries
DOI:10.1002/anie.199726201
日期:1997.12.15
Asymmetric conjugate additions to 1,1′-diactivated cyclic enones—a comparative study
作者:Xiaoping Tang、Alexander J. Blake、William Lewis、Simon Woodward
DOI:10.1016/j.tetasy.2009.07.006
日期:2009.8
A study of copper-phosphoramidite-catalysed ZnR2 and AlR3 additions to 1,1'-dicarbonyl-activated cyclic Michael acceptors has revealed high enantioselectivities for AlR3 (R = Me, Et) 1,4-addition to a range of 3-acylcoumarins (85-98% ee, trans:cis similar to 90:10) using commercial OF readily available ligands. Large substituents at the 6-position, and to some extent at the 5-position, of the coumarin are less well tolerated, nor is truncation of the coumarin motif to a comparable 2-acylcyclohexenone (ee values up to 78%). (C) 2009 Elsevier Ltd. All rights reserved.