Soluble {[Rh2(μ-OOCCH3)2(dbbpy)2][BF4]}n molecular wire and [Rh2(μ-OOCCH3)2(dbbpy)2L2]2+ complexes; dbbpy = 4,4′-di-tert-butyl-2,2′-bipyridine: Synthesis and physicochemical characterization