Abstract
A Ru(II) complex having tris(2-pyridylmethl)amine (TPA) and 2,2'-bipyridine (bpy), [Ru(TPA)(bpy)]X(2) (X = ClO(4), PF(6)), exhibited a severe distortion of the coordination of the axial pyridine moiety of TPA due to steric hindrance. The complex showed interesting dissociation-binding behavior of the axial pyridine arm to form a solvent adduct with TPA ligation in a unique meridional tridentate fashion. The complex undergoes thermal dissociation to form solvent-coordinated species via an S(N)2-like mechanism with activation energy of 117 kJ/mol. In contrast, the complex showed reversible photochemical dissociation and rebinding via an S(N)1-like mechanism by MLCT irradiation. The photochemical dissociation was accelerated approximately 200-fold faster than the thermal process. The dissociation process involves selective binding behavior toward external ligands (solvents) with pi-acceptor character, which is indispensable, and no sigma-donating molecules could bind to the Ru(II) center. The guest molecule can be released upon photoirradiation after its thermal binding.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.