title: Isolation of neutral mononuclear copper complexes stabilized by two cyclic (alkyl)(amino)carbenes.
abstract: Two (cAAC)2Cu complexes, featuring a two-coordinate copper atom in the formal oxidation state zero, were prepared by reducing (Et2-cAAC)2Cu(+)I(-) with metallic sodium in THF, and by a one-pot synthesis using Me2-cAAC, Cu(II)Cl2, and KC8 in toluene in a molar ratio of 2:1:2, respectively. Both complexes are highly air and moisture sensitive but can be stored in the solid state for a month at room temperature. DFT calculations showed that in these complexes the copper center has a d(10) electronic configuration and the unpaired electron is delocalized over two carbene carbon atoms. This was further confirmed by the EPR spectra, which exhibit multiple hyperfine lines due to the coupling of the unpaired electron with (63,65)Cu isotopes, (14)N, and (1)H nuclei.
authors.affiliation: UCSD-CNRS Joint Research Chemistry Laboratory (UMI 3555), Department of Chemistry and Biochemistry, University of California-San Diego , La Jolla, California 92093-0343, United States.
authors.forename: David S
authors.initials: DS
authors.lastname: Weinberger
authors.forename: Nurul
authors.initials: N
authors.lastname: Amin Sk
authors.forename: Kartik Chandra
authors.initials: KC
authors.lastname: Mondal
authors.forename: Mohand
authors.initials: M
authors.lastname: Melaimi
authors.forename: Guy
authors.initials: G
authors.lastname: Bertrand
authors.forename: A Claudia
authors.initials: AC
authors.lastname: Stückl
authors.forename: Herbert W
authors.initials: HW
authors.lastname: Roesky
authors.forename: Birger
authors.initials: B
authors.lastname: Dittrich
authors.forename: Serhiy
authors.initials: S
authors.lastname: Demeshko
authors.forename: Brigitte
authors.initials: B
authors.lastname: Schwederski
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Kaim
authors.forename: Paul
authors.initials: P
authors.lastname: Jerabek
authors.forename: Gernot
authors.initials: G
authors.lastname: Frenking
mesh_terms: D000478:Alkylation; D000588:Amines / Q000138:chemical synthesis / Q000737:chemistry*; D056831:Coordination Complexes / Q000138:chemical synthesis / Q000737:chemistry*; D003300:Copper / Q000737:chemistry*; D003500:Cyclization; D004578:Electron Spin Resonance Spectroscopy; D008697:Methane / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000737:chemistry; D008958:Models, Molecular; D010084:Oxidation-Reduction
chemical_list: D000588:Amines; D056831:Coordination Complexes; C030011:carbene; D003300:Copper; D008697:Methane