Mechanistic Investigations into the Enantioselective Conia-Ene Reaction Catalyzed by Cinchona-Derived Amino Urea Pre-Catalysts and Cu<sup>I</sup>
作者:Filippo Sladojevich、Ángel L. Fuentes de Arriba、Irene Ortín、Ting Yang、Alessandro Ferrali、Robert S. Paton、Darren J. Dixon
DOI:10.1002/chem.201200832
日期:2013.10.11
Conia‐ene cyclization of alkyne‐tethered β‐ketoesters is efficiently catalyzed by the combination of cinchona‐derived amino‐urea pre‐catalysts and copper(I) salts. The reaction scope is broad and a series of substrates can be efficiently cyclized with high yields and enantioselectivities. Herein, we present a detailed mechanistic study based on experimental considerations and quantum mechanical calculations
作者:Andrew F. Kyle、Pavol Jakubec、Dane M. Cockfield、Ed Cleator、John Skidmore、Darren J. Dixon
DOI:10.1039/c1cc13665h
日期:——
addition, a nitro-Mannich/lactamization cascade, a furan N-acyliminium cyclisation, a sequential alkyne RCM/syn-reduction and an alkene RCM has allowed a 19 step, highly stereoselective synthesis of (-)-nakadomarin A.
Asymmetric Indoline Synthesis via Intramolecular Aza-Michael Addition Mediated by Bifunctional Organocatalysts
作者:Ryota Miyaji、Keisuke Asano、Seijiro Matsubara
DOI:10.1021/ol401538b
日期:2013.7.19
A novel method for the asymmetric synthesis of 2-substituted indolines, employing bifunctional amino(thio)urea catalysts, was developed. The reaction proceeded via an intramolecular aza-Michael addition mediated by activation through hydrogen bonding. The catalytic process was shown to be highly versatile and applicable to a wide range of substrates due to the flexible catalytic mechanism utilizing a noncovalent interaction.