Three heteroleptic copper(I) complexes with [Cu(P^˄P)N₂]⁺ structure and their fluorescence sensing for VOCs

The design and research of luminescent volatile organic compound (VOC) fluorescent sensing materials are great significance challenge. We report herein the ligand substitution reaction VOC new heteroleptic [Cu(P ˄ P)N 2 ] + type copper(I) complexes. Firstly, three complexes 1 – 3 were designed by utilizing a chelate diphosphine 4,5‐bis(diphenylphosphino)‐9,9‐dimethylxanthene (Xantphos) synthesized different N‐containing ligands 4‐PBO ( ), 3‐PBO 4,4′‐Bipy ) (4‐PBO = 2‐(4′‐pyridyl)‐benzoxazole, 2‐(3′‐pyridyl)‐benzoxazole, 4,4′‐bipyridine), respectively. Three characterized elemental analysis, spectroscopic analysis (IR, UV–Vis), single‐crystal X‐ray diffraction (SCXRD), photoluminescence study. SCXRD study revealed that both exhibit molecular structure with tetrahedral complex cation hexafluorophosphate anion, while differs in its is binuclear bridged 4,4′‐bipyridine. present supramolecular ribbon, dimer, framework structure, Some differences their UV–Vis absorption spectra explained TD‐DFT calculation wavefunction analysis. It found has an abnormal luminescence blue shift, mechanism through high‐energy T excited state proposed calculation. Based on , test strip was developed, fast selective pyridine vapor quenching successfully realized. material also studied, it should be attributed to photoinduced electron transfer (PET) mechanism.