title: Synthesis and characterization of phosphorescent two-coordinate copper(i) complexes bearing diamidocarbene ligands.
abstract: The photophysical properties of four, two-coordinate, linear diamidocarbene copper(i) complexes, [(DAC)2Cu][BF4] (1), (DAC)CuOSiPh3(2), (DAC)CuC6F5(3) and (DAC)Cu(2,4,6-Me3C6H2) (4) (DAC = 1,3-bis(2,4,6-trimethylphenyl)-5,5-dimethyl-4,6-diketopyrimidinyl-2-ylidene) have been investigated. Complex 1 shows a high photoluminescence quantum efficiency (ΦPL) in both the solid state (ΦPL= 0.85) and in CH2Cl2solution (ΦPL= 0.65). The emission band of 1, both as a crystalline solid and in solution, is narrow (fwhm = 2300 cm-1) relative to the emission bands of 2 (fwhm = 2900 cm-1) and 3 (fwhm = 3700 cm-1). Complexes 2 and 3 are each brightly luminescent in the solid state (ΦPL= 0.62 and 0.18, respectively), but markedly less so in CH2Cl2solution (ΦPL= 0.03 and <0.01, respectively). Complex 4 is not emissive in either the solid state or in solution. Phosphorescence of 1 in CH2Cl2solution shows negligible quenching by oxygen in CH2Cl2solution. This insensitivity to quenching is attributed to the excited state redox potential being insufficient for electron transfer to oxygen.
authors.affiliation: Department of Chemistry, University of Southern California, Los Angeles, California 90089, USA. met@usc.edu.
authors.forename: Shuyang
authors.initials: S
authors.lastname: Shi
authors.affiliation: Department of Chemistry, University of Bath, Claverton Down, Bath BA2 7AY, UK. M.K.Whittlesey@bath.ac.uk.
authors.forename: Lee R
authors.initials: LR
authors.lastname: Collins
authors.affiliation: Department of Chemistry, University of Bath, Claverton Down, Bath BA2 7AY, UK. M.K.Whittlesey@bath.ac.uk.
authors.forename: Mary F
authors.initials: MF
authors.lastname: Mahon
authors.affiliation: Department of Chemistry, University of Southern California, Los Angeles, California 90089, USA. met@usc.edu.
authors.forename: Peter I
authors.initials: PI
authors.lastname: Djurovich
authors.affiliation: Department of Chemistry, University of Southern California, Los Angeles, California 90089, USA. met@usc.edu.
authors.forename: Mark E
authors.identifier: http://orcid.org/0000-0002-7764-4096
authors.initials: ME
authors.lastname: Thompson
authors.affiliation: Department of Chemistry, University of Bath, Claverton Down, Bath BA2 7AY, UK. M.K.Whittlesey@bath.ac.uk.
authors.forename: Michael K
authors.initials: MK
authors.lastname: Whittlesey