Luminescent heteroleptic copper(I) complexes with polydentate benzotriazolyl-based ligands


Bis(benzotriazol-1-yl)phenylmethane CHPh(btz)2 and tris(benzotriazol-1-yl)methane CH(btz)3 were used as N-donor ligands to prepare luminescent heteroleptic copper(I) complexes. [Cu{CHPh(btz)2}(PPh3)2][BF4] and [Cu{CHPh(btz)2}(DPEphos)][BF4] (DPEphos = bis[(2-diphenylphosphino)phenyl] ether) were obtained from the corresponding borohydride complexes [Cu(BH4)(PPh3)2] and [Cu(BH4)(DPEphos)] and tetrafluoroboric acid. [Cu{CH(btz)3}(PPh3)][BF4] and [Cu{CH(btz)3}(PiPr3)][BF4] were prepared from the acetonitrile complex [Cu(NCCH3)4][BF4]. The complexes exhibited bright yellow or orange emissions upon excitation with near-UV and violet light. The photoluminescent properties were attributed to metal-to-ligand charge transfer transitions on the basis of experimental data and DFT calculations.

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CACTI (University of Vigo) is gratefully acknowledged for X-ray data collection. We acknowledge Università Ca’ Foscari Venezia for financial support (Bando Spin 2018, D. R. 1065/2018 prot. 67416) and CINECA (COLUMN project 2020) for the availability of computing resources.

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Ferraro, V., Castro, J., Agostinis, L. et al. Luminescent heteroleptic copper(I) complexes with polydentate benzotriazolyl-based ligands. Transit Met Chem (2021).

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