Copper-Catalyzed Enantioselective Research Articles

Copper-catalyzed enantioselective conjugate addition of diethylzinc to acyclic enones in the presence of planar-chiral phosphaferrocene-oxazoline ligands.

[reaction: see text] A new subclass of chiral phosphaferrocene-oxazoline ligands has been applied to the copper-catalyzed asymmetric conjugate addition of diethylzinc to acyclic enones, furnishing good enantioselectivity. The ligand design readily lends itself to modification, thereby facilitating optimization of ee. Although the dominant stereocontrol element in these 1,4-addition processes is the central chirality of the oxazoline subunit of the ligand, not the planar chirality of the phosphaferrocene, altering the phosphaferrocene subunit can provide useful enhancement of enantioselectivity.

ChemInform Abstract: Optimization of New Chiral Ligands for the Copper‐Catalyzed Enantioselective Conjugate Addition of Et2Zn to Nitroolefins by High‐Throughput Screening of a Parallel Library.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform Abstract: First Enantioselective Catalyst Based on a Chiral Terpyridine: Synthesis of New C2-Symmetric 2,2′:6′,2′′-Terpyridine Ligands and Copper-Catalyzed Enantioselective Cyclopropanation of Alkenes

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Novel Chiral Di-2-pyridyl Ketone Ligands: Crystal Structure of a Copper Complex and its Activity in the Copper-Catalyzed Enantioselective Cyclopropanation of Styrene

New C2-symmetric chiral di-2-pyridyl ketones were prepared from readily available chiral bromopyridines. Their complexes with copper were synthesized and characterized by X-ray crystallography. The copper complexes were prepared in situ with the triflate anion and were found to be active in the catalysis of cyclopropanation with diazo esters and alkenes. Reaction yields were excellent and enantioselectivities of up to 61% were observed.

Novel Chiral Di-2-pyridyl Ketone Ligands: Crystal Structure of a Copper Complex and its Activity in the Copper-Catalyzed Enantioselective Cyclopropanation of Styrene

New C2-symmetric chiral di-2-pyridyl ketones were prepared from readily available chiral bromopyridines. Their complexes with copper were synthesized and characterized by X-ray crystallography. The copper complexes were prepared in situ with the triflate anion and were found to be active in the catalysis of cyclopropanation with diazo esters and alkenes. Reaction yields were excellent and enantioselectivities of up to 61% were observed.

ChemInform Abstract: Discovery of a New Efficient Chiral Ligand for Copper‐Catalyzed Enantioselective Michael Additions by High‐Throughput Screening of a Parallel Library.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Discovery of a New Efficient Chiral Ligand for Copper-Catalyzed Enantioselective Michael Additions by High-Throughput Screening of a Parallel Library

Discovery of a New Efficient Chiral Ligand for Copper-Catalyzed Enantioselective Michael Additions by High-Throughput Screening of a Parallel Library

Copper-Catalyzed Enantioselective Michael Additions: Recent Progress with New Phosphorus Ligands.

A breakthrough in copper-catalyzed enantioselective Michael additions was achieved recently by Feringa et al. by using the chiral phosphorus amidite 1. With few mol % of this ligand and copper(II) triflate, highly enantioselective 1,4-additions of diorganozinc reagents to numerous cyclic enones can be carried out.