title: Dinuclear N-heterocyclic carbene complexes of silver(I), derived from imidazolium-linked cyclophanes.
abstract: The synthesis of four new silver complexes of bidentate N-heterocyclic carbenes, derived from imidazolium-linked cyclophanes, has been achieved via a simple complexation reaction of the imidazolium-linked cyclophanes with the basic metal source Ag(2)O. The cyclophane structures contain two imidazolyl links between ortho-, meta- and mixed ortho/meta-substituted aromatic rings. The new silver carbene systems are thermally stable and have been characterised by NMR spectroscopy and X-ray crystallography. Three of the complexes have a dimeric structure of the form [L(2)Ag(2)](2+) in the solid state that is rigid on the NMR timescale in solution. The fourth complex has a neutral structure of the form [L(AgBr)(2)], the NMR studies suggesting some lability of the L-Ag bonding in solution.
authors.affiliation: Chemistry M313, The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia. mvb@chem.uwa.edu.au.
authors.forename: Murray V
authors.initials: MV
authors.lastname: Baker
authors.forename: David H
authors.initials: DH
authors.lastname: Brown
authors.forename: Rosenani A
authors.initials: RA
authors.lastname: Haque
authors.forename: Brian W
authors.initials: BW
authors.lastname: Skelton
authors.forename: Allan H
authors.initials: AH
authors.lastname: White