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.
Induction of Axial Chirality in 8-Arylquinolines through Halogenation Reactions Using Bifunctional Organocatalysts
作者:Ryota Miyaji、Keisuke Asano、Seijiro Matsubara
DOI:10.1002/chem.201701707
日期:2017.7.26
The enantioselective syntheses of axially chiral heterobiaryls were accomplished through the aromatic electrophilic halogenation of 3‐(quinolin‐8‐yl)phenols with bifunctional organocatalysts that control the molecular conformations during successive halogenations. Axially chiral quinoline derivatives, which have rarely been synthesized in an enantioselective catalytic manner, were afforded in moderate‐to‐good
A New Family of Cinchona-Derived Bifunctional Asymmetric Phase-Transfer Catalysts: Application to the Enantio- and Diastereoselective Nitro-Mannich Reaction of Amidosulfones
作者:Kayli M. Johnson、Matt S. Rattley、Filippo Sladojevich、David M. Barber、Marta G. Nuñez、Anna M. Goldys、Darren J. Dixon
DOI:10.1021/ol300779x
日期:2012.5.18
family of bifunctional H-bond donor phase-transfer catalysts derived from cinchona alkaloids has been developed and evaluated in the enantio- and diastereoselective nitro-Mannich reaction of in situgenerated N-Boc-protected imines of aliphatic, aromatic, and heteroaromatic aldehydes. Under optimal conditions, good reactivity and high diastereoselectivities (up to 24:1 dr) and enantioselectivities (up to