Imidazol(in)ium Hydrogen Carbonates as a Genuine Source of N-Heterocyclic Carbenes (NHCs): Applications to the Facile Preparation of NHC Metal Complexes and to NHC-Organocatalyzed Molecular and Macromolecular Syntheses
VIGNOLLE, Joan
Laboratoire de Chimie des Polymères Organiques [LCPO]
Team 1 LCPO : Polymerization Catalyses & Engineering
Laboratoire de Chimie des Polymères Organiques [LCPO]
Team 1 LCPO : Polymerization Catalyses & Engineering
TATON, Daniel
Laboratoire de Chimie des Polymères Organiques [LCPO]
Team 1 LCPO : Polymerization Catalyses & Engineering
< Reduce
Laboratoire de Chimie des Polymères Organiques [LCPO]
Team 1 LCPO : Polymerization Catalyses & Engineering
Language
en
Article de revue
This item was published in
Journal of the American Chemical Society. 2012, vol. 134, n° 15, p. 6776-6784
American Chemical Society
English Abstract
Anion metathesis of imidazol(in)ium chlorides with KHCO3 afforded an easy one step access to air stable imidazol(in)ium hydrogen carbonates, denoted as [NHC(H)][HCO3]. In solution, these compounds were found to be in ...Read more >
Anion metathesis of imidazol(in)ium chlorides with KHCO3 afforded an easy one step access to air stable imidazol(in)ium hydrogen carbonates, denoted as [NHC(H)][HCO3]. In solution, these compounds were found to be in equilibrium with their corresponding imidazol(in)ium carboxylates, referred to as N-heterocyclic carbene (NHC)-CO2 adducts. The [NHC(H)][HCO3] salts were next shown to behave as masked NHCs, allowing for the NHC moiety to be readily transferred to both organic and organometallic substrates, without the need for dry and oxygen-free conditions. In addition, such [NHC(H)][HCO3] precursors were successfully investigated as precatalysts in two selected organocatalyzed reactions of molecular chemistry and polymer synthesis, namely, the benzoin condensation reaction and the ring-opening polymerization of D,L-lactide, respectively. The generation of NHCs from [NHC(H)][HCO3] precursors occurred via the formal loss of H2CO3 via a concerted low energy pathway, as substantiated by Density Functional Theory (DFT) calculations.Read less <
English Keywords
TRANSFER AGENTS
LIGAND PRECURSORS
LIVING POLYMERIZATION
ORGANOMETALLIC CATALYSIS
IMIDAZOLIUM CARBOXYLATES
OLEFIN METATHESIS
METATHESIS CATALYSTS
RING-OPENING POLYMERIZATION
IONIC LIQUIDS
STRUCTURAL-CHARACTERIZATION
Origin
Hal imported