Journal ArticleDOI
N-Heterocyclic Carbenes−Borane Complexes: A New Class of Initiators for Radical Photopolymerization
Mohamad-Ali Tehfe,Malika Makhlouf Brahmi,Jean Pierre Fouassier,Dennis P. Curran,Max Malacria,Louis Fensterbank,Emmanuel Lacôte,Jacques Lalevée +7 more
TLDR
In this article, N-heterocyclic carbene-boryl radicals (NHC-BH2•) derived from readily available N-Heterocyclics carbene−boranes are found to be efficient initiators for acrylate photopolymerization.Abstract:
Newly discovered N-heterocyclic carbene-boryl radicals (NHC-BH2•) derived from readily available N-heterocyclic carbene−boranes are found to be efficient initiators for acrylate photopolymerization. Laser flash photolysis (LFP) experiments were used to generate three carbene-boryl radicals, which were characterized by their transient absorption spectra with the aid of DFT calculations. Rate constants were measured for the generation of the carbene-boryl radicals by hydrogen abstraction with tert-butoxyl radical, a ketophosphonyl radical, and triplet benzophenone. Rate constants were also measured for the reactions of the carbene-boryl radicals with oxygen, three alkenes, two alkyl chlorides, and diphenyliodonium hexafluorophosphate. The observed trends were interpreted with the aid of measured oxidation potentials of the carbene−boranes and calculated ionization potentials of the carbene-boryls. N-Heterocyclic carbene−boranes show excellent potential as both photopolymerization co-initiators and mediators...read more
Citations
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Journal ArticleDOI
Stable singlet carbenes as mimics for transition metal centers
TL;DR: This perspective summarizes recent results, which demonstrate that stable carbenes can activate small molecules and stabilize highly reactive intermediates and main group elements in the zero oxidation state and paramagnetic species.
Journal ArticleDOI
NHCs in Main Group Chemistry.
Vitaly Nesterov,Dominik Reiter,Prasenjit Bag,Philipp Frisch,Richard Holzner,Amelie Porzelt,Shigeyoshi Inoue +6 more
TL;DR: A general overview of the chemistry of low-coordinate main group element compounds, basic synthetic approaches, key features of NHC-main group element adducts, and might be useful for the broad research community are given.
Journal ArticleDOI
N-Heterocyclic carbenes (NHCs) as organocatalysts and structural components in metal-free polymer synthesis
Mareva Fevre,Mareva Fevre,Julien Pinaud,Julien Pinaud,Yves Gnanou,Yves Gnanou,Joan Vignolle,Joan Vignolle,Daniel Taton,Daniel Taton +9 more
TL;DR: This review presents the electronic properties of N-heterocyclic carbenes, their main synthetic methods, their handling, and their reactivity, as well as the use of NHCs as structural components of the polymer chain.
Journal ArticleDOI
Carbene-stabilized main group radicals and radical ions
TL;DR: This review covers examples in the literature dealing with the most recent application of stable singlet carbenes, namely their use to stabilize radicals and radical ions that are otherwise unstable.
Journal ArticleDOI
Synthesis and reactions of N-heterocyclic carbene boranes.
Dennis P. Curran,Andrey Solovyev,Malika Makhlouf Brahmi,Louis Fensterbank,Max Malacria,Emmanuel Lacôte +5 more
TL;DR: This Review provides comprehensive coverage of the synthesis, characterization, and reactions of NHC-boranes.
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