Chiral Organic Ion Pair Catalysts Assembled Through a ... - Science
Aug 27, 2009 · Here, we report that a chiral tetraaminophosphonium cation, two phenols, and a phenoxide anion appear to self-assemble into a catalytically active supramolecular architecture through intermolecular hydrogen bonding. The structure of the resulting molecular assembly was determined in the solid state by means of x-ray diffraction analysis.
A chiral ion-pair photoredox organocatalyst: enantioselective anti ...
A chiral ion-pair photoredox organocatalyst was reported to facilitate visible-light-meditated asymmetric anti-Markovnikov hydroetherification of alkenols with high reactivity and moderate enantioselectivity.
Electricity-driven asymmetric bromocyclization enabled by chiral ...
Jan 23, 2023 · Asymmetry induced by weak interactions with a chiral catalyst in an electrochemical medium remains challenging due to compatibility issues related to solvent polarity, electrolyte interference,...
Chiral Diselenophosphoric Acids for Ion Pair Catalysis: A Novel ...
May 15, 2024 · The activation of poorly reactive substrates via strong chiral acids is a central topic in asymmetric ion pair catalysis these days. Despite highly successful scaffolds such as N-triflylphosphoramides, these catalysts either lack C2-symmetry or provide multiple H-bond acceptor sites, leading to lower ee values for certain reactions. We present ...
Chiral Organic Contact Ion Pairs in Metal-Free Catalytic …
Feb 28, 2011 · The concept relies on chiral contact ion-pair catalysis, in which the chiral organic counteranion of an allylic carbocation induces high enantioselectivities and allows access to biologically relevant chromenes in good yields and with excellent enantioselection.
The progression of chiral anions from concepts to applications in ...
Jul 24, 2012 · New concepts for the construction and mode of operation of chiral catalysts have the potential to open up previously inaccessible reaction space. The recognition and categorization of distinct...
A chiral pentanidium and pyridinyl-sulphonamide ion pair as an ...
Nov 9, 2023 · In this study, we report the successful development of a stable chiral pentanidium pyridinyl-sulphonamide ion pair as a nucleophilic organocatalyst for asymmetric Steglich rearrangement. The ion pair catalyst demonstrated excellent performance, leading to enantioenriched products with up to 99% ee through simple alterations of the achiral anions.
A Powerful Chiral Counterion Strategy for Asymmetric ... - Science
Jul 27, 2007 · Furthermore, we show that the chiral counterion can be combined additively with chiral ligands to enable an asymmetric transformation that cannot be achieved by either method alone. This concept of relaying chiral information via an ion pair should be applicable to a vast number of metal-mediated processes.
Ion-paired chiral ligands for asymmetric palladium catalysis
Apr 1, 2012 · Here, we report a new strategy for the design of a chiral ligand for asymmetric transition-metal catalysis; our approach is based on the development of an achiral cationic ammonium–phosphine...
Chiral ion pairs in catalysis: lithium salts of chiral metallocomplex ...
Aug 12, 2009 · The ion pairing of these anions to a lithium cation can be used to induce asymmetry into lithium-catalyzed trimethylsilylcyanation of aldehydes and Michael reactions. The influence of the temperature, solvent polarity and structural modification of the chiral anion on the enantioselectivity of the catalysis has been investigated.