Synthesis and dynamic behavior of an anthyridine-ligated ruthenium complex.

A ruthenium complex containing a 1,9,10-anthyridine derivative, [Ru(L)(bpy)2](PF6)2 ([1](PF6)2; L = 1,13,14-triazadibenz[a,j]anthracene, bpy = 2,2'-bipyridyl), was synthesized. X-ray crystal structural analysis of [1](PF6)2 showed that L is coordinated to the Ru center as a bidentate ligand. When [1](PF6)2 was dissolved in acetonitrile, a new complex incorporating one acetonitrile molecule, [Ru(L)(CH3CN)(bpy)2](PF6)2 ([2](PF6)2), was formed. X-ray crystallographic data revealed that, in [2](PF6)2, L is coordinated to the Ru center in a monodentate fashion. The coordinated L in [2](PF6)2 shows a unique haptotropic rearrangement in an acetonitrile solution.