Complexation to [Ru(bpy)2]2+: the trick to functionalize 3,3′-disubstituted-2,2′-bipyridine

While many papers reported the synthesis and chemical transformations of x,x′-disubstituted-2,2′-bipyridine with x = 4, 5 or 6, this is not the case when x = 3. Though, such 3,3′-disubstituted-2,2′-bipyridines would be a useful building block for the design of new original complexes. Here we report the results of our investigation concerning the synthesis of members of this family. This study led to the formation of several [(2,2′-bipyridine)2Ru(3,3′-dialkylated-2,2′-bipyridine)]2+ complexes highlighting a surprising chemical behaviour of the 3,3′-disubstituted-2,2′-bipyridine ligand compared to its 4,4′, 5,5′ and 6,6′-homologues.