Solution and solid-state light-induced transformations in heterometallic vanadium-ruthenium nitrosyl complex

• Published in: Journal of photochemistry and photobiology. A, Chemistry. Chemistry., 2021-02, Vol.407, p.113044, Article 113044
• Main Authors: Fomenko, Iakov S., Mikhailov, Artem A., Vorobyev, Vasily, Kuratieva, Natalia V., Kostin, Gennadiy A., Schaniel, Dominik, Nadolinny, Vladimir A., Gushchin, Artem L.
• Format: Article
• Language: English
• Subjects: Chemical Sciences; Coordination chemistry; Isomerization; Metastable states; Nitrosyl; Other; Oxidovanadium complexes; Ruthenium; Vanadium
• ISSN: 1010-6030; 1873-2666
• DOI: 10.1016/j.jphotochem.2020.113044

[Display omitted] •Complex [Ru(NO)(NO2)2(μ-NO2)(μ−CH3COO)(μ-O)VO(dbbpy)]·CH3CN is platform, releasing NO in a solution under light exposure.•The irradiation of complex in solid state induce formation of Ru-ON linkage isomer reversibly decays to Ru-NO at 120−140 K.•The presence of vanadium influences the photochemical properties of ruthenium nitrosyl both in solid phase and in solution. The work is devoted to the preparation and photochemical investigations of the novel binuclear heterometallic complex [Ru(NO)(NO2)2(μ-NO2)(μ−CH3COO)(μ-O)VO(dbbpy)]·CH3CN (dbbpy - 4,4′-di-tert-butyl-2,2′-bipyridyl), which is obtained with quantitative yield. The structure of the complex is determined by single crystal X-ray diffraction and by DFT calculations. On the one hand, irradiation at 445 nm of an acetonitrile solution of the complex leads to a NO photo-release reaction. The light excitation induces the charge transfer from NO2 and dbbpy ligands to the antibonding orbitals of ON-Ru-O-V chain, leading to the NO release, which is confirmed by the DFT. The quantum yield of the Ru-NO photo-cleavage is 0.57 ± 0.05 %. The products of the photolysis (NO and paramagnetic RuIII complex) are confirmed by the Griess test and EPR-spectroscopy. On the other hand, the irradiation of the complex in the solid phase at 10 K results in the formation of the metastable bond isomer Ru-ON (MS1), which is detected by the infrared spectroscopy. The stretching vibration of the ν(NO) band of MS1 (1750 cm−1) is shifted by 150 cm−1 to lower energy with respect to the ν(NO) band of the ground state GS (1900 cm−1). The population of the MS1 is about 5%. MS1 thermally decays at 120−140 K back to the GS. Hence, this complex represents a bifunctional platform, which can release nitric oxide in solution and reversibly switch the NO ligand coordination in the solid state. It is shown, that the presence of vanadium strongly influences the photochemical properties of ruthenium nitrosyl both in the solid phase and in solution.