title: Selective Activation of Fluoroalkenes with N-Heterocyclic Carbenes: Synthesis of N-Heterocyclic Fluoroalkenes and Polyfluoroalkenyl Imidazolium Salts.
abstract: Selective reactions between nucleophilic N,N'-diaryl-heterocyclic carbenes (NHCs) and electrophilic fluorinated alkenes afford NHC fluoroalkenes in high yields. These stable compounds undergo efficient and selective fluoride abstraction with Lewis acids to give polyfluoroalkenyl imidazolium salts. These salts react at Cβ with pyrrolidine to give ammonium fluoride-substituted salts, which give rise to conjugated imidazolium-enamine salts through loss of HF. Alternatively, reaction with 4-(dimethylamino)-pyridine provides a Cα-pyridinium-substituted NHC fluoroalkene. These compounds were studied using multinuclear NMR spectroscopy, mass spectrometry, and X-ray crystallography. Insight into their electronic structure and reactivity was gained through the use of DFT calculations.
authors.affiliation: Department of Chemistry and Biomolecular Sciences and Centre for Catalysis Research and Innovation, University of Ottawa, 30 Marie Curie, Ottawa, Ontario, K1N 6N5, Canada.
authors.forename: Matthew C
authors.initials: MC
authors.lastname: Leclerc
authors.affiliation: Department of Chemistry and Biomolecular Sciences and Centre for Catalysis Research and Innovation, University of Ottawa, 30 Marie Curie, Ottawa, Ontario, K1N 6N5, Canada.
authors.forename: Serge I
authors.initials: SI
authors.lastname: Gorelsky
authors.affiliation: Department of Chemistry and Biomolecular Sciences and Centre for Catalysis Research and Innovation, University of Ottawa, 30 Marie Curie, Ottawa, Ontario, K1N 6N5, Canada.
authors.forename: Bulat M
authors.initials: BM
authors.lastname: Gabidullin
authors.affiliation: Department of Chemistry and Biomolecular Sciences and Centre for Catalysis Research and Innovation, University of Ottawa, 30 Marie Curie, Ottawa, Ontario, K1N 6N5, Canada.
authors.forename: Ilia
authors.initials: I
authors.lastname: Korobkov
authors.affiliation: Department of Chemistry and Biomolecular Sciences and Centre for Catalysis Research and Innovation, University of Ottawa, 30 Marie Curie, Ottawa, Ontario, K1N 6N5, Canada. rbaker@uottawa.ca.
authors.forename: R Tom
authors.initials: RT
authors.lastname: Baker
keywords: NMR spectroscopy; carbenes; fluoroalkenes; imidazolium; pyrrolidine