Synthesis, crystal structures and luminescent properties of the copper(I) pyrazolonate complexes

New copper(I) complexes with pyrazolonate ligands [Cu(Pr-i-PMP)(DPEphos)] (1) and [Cu(Bu-t-PMP) (DPEphos)] (2) (Pr-i-PMP = 1-phenyl-3-methyl-4-isobutyryl-5-pyrazolonato, Bu-t-PMP = 1-phenyl-3-methyl-(2,2-dimethylpropan-1-oyl)-5-pyrazolonato; DPEphos = bis[2-(diphenylphosphino)-pheny]ether) were synthesized and structurally characterized. An unusual eta(1) cocoordination of pyrazolonate ligand to the copper atom was found in complex 2. Photo-and electroluminescent properties of the synthesized compounds were investigated. In crystalline form compounds 1 and 2 revealed dual emission consisting of the bands at 445-450 and 485-488 nm which were assigned to transitions from the S-1 and T-1 states. DFT and TD DFT calculations as well as electrochemical studies correlate with the photophysical data. Synthesized copper(I) complexes generated electroluminescence of yellowish-orange (1) and yellow (2) colors with the maximum luminance of 286 and 39 cd/m(2), respectively. (C) 2014 Elsevier B.V. All rights reserved.