Link to glow - iEDDA conjugation of a Ruthenium(II) tetrazine complex leading to dihydropyrazine and pyrazine complexes with improved 1O2 formation ability

Journal of Photochemistry and Photobiology

Pascal Wintergerst¹  Sven Rau¹  Nicolas Meitinger²  Carolin Müller²  Benjamin Dietzek-Ivanšić³  Shruthi Santhosh Nair³ 

[1] Leibniz Institute of Photonic Technology, Research Department Functional Interfaces, Albert-Einstein-Str. 9, Jena 07745, Germany;Friedrich Schiller University Jena, Institute of Physical Chemistry, Helmholtzweg 4, Jena 07743, Germany;Institute of Inorganic Chemistry I, Ulm University, Albert-Einstein-Allee 11, Ulm 89081, Germany;

关键词: Singlet-oxygen;    Transient absorption spectroscopy;    Ruthenium complex;    Tetrazine;    Pyrazine;    TD-DFT;   

DOI  :  

来源: DOAJ

【 摘 要 】

The synthesis and photophysical properties of the Ru-polypyridyl type complex [(tbbpy)2Ru(bptz)]2+ (Ru-bptz, tbbpy: 4,4’-di-tert-butyl-2,2’-bipyridine, bptz: 2,6-dipyrido-1,2,4,5-tetrazine), and the complexes [(tbbpy)2Ru(L)]2+ formed by inverse electron demand Diels Alder reaction (iEDDA) of Ru-bptz with with alkenes and alkynes, where L is 3,6-dipyrido-2,5-dihydropyridazine (bpdhpn) or 3,6-dipyrido-pyridazine (bppn) are described. A combination of steady-state and time-resolved spectroscopy complemented by the computation of state-specific absorption properties by means of time-dependent density functional theory reveals that the intense visible absorption band stems from Ru → tbbpy and Ru → L metal-to-ligand charge-transfer (MLCT) excitations. The studies show that lowest-lying L-centered MLCT states (3MLCTL) show comparably low emission quantum yields (3–9%) and lifetimes (90–150 ns). This correlates with the singlet oxygen generation ability, following the trend: Ru-bppn > Ru-bpdhpn > Ru-bptz.

【 授权许可】

Unknown