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Updated: Oct 21, 2025

The Synthesis, Characterization and Reactivity of a Series of Ruthenium N-triphosPh Complexes
Published on: April 10, 2015
A Synthetic Route to a Ruthenium Complex via Successive Photosubstitution Reactions
Masanari Hirahara1, Yasushi Umemura2
1Department of Applied Chemistry, Faculty of Engineering, Osaka Institute of Technology, 5-16-1 Omiya, Asahi-ku, Osaka 535-8585, Japan.
Abstract:
Photosubstitution reactions of cis-[Ru(bpy)2(MeCN)2]2+ with a pyrazole ligand (pzH) were studied under various conditions toward the development of a photochemical synthetic route to polypyridyl ruthenium complexes (bpy = 2,2'-bipyridine). In the absence of a base, light irradiation of an acetonitrile solution of pyrazole and cis-[Ru(bpy)2(MeCN)2]2+ gave a mixture of the reactant and cis-[Ru(bpy)2(pzH)(MeCN)]2+. In the presence of a mild base such as N,N-dimethylaminopyridine, a second photosubstitution from cis-[Ru(bpy)2(pzH)(MeCN)]2+ to cis-[Ru(bpy)2(pz)(pzH)]+ (1b) was greatly enhanced, as confirmed by UV-vis and 1H nuclear magnetic resonance spectroscopy. The yields of 1b were increased in solvents with moderate coordinating properties, such as acetone. The successive photosubstitution reaction was observed using a stoichiometric amount of pyrazole.
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