Fac-ruthenium(II) tris-(5-carboxy-2,2'-bipyridine) has been synthesised as a single geometric isomer for the first time, and proves to be a good "building-block" to introduce new functionality with retention of the isomeric integrity.
Fletcher, N., Nieuwenhuyzen, M., Prabarahan, R., & Wilson, A. (2002). The isolation and secondary functionalisation of fac-tris2,2'-bipyridine complexes of ruthenium(II). Chemical Communications, 2002, 1188-1189. https://doi.org/10.1039/b202886g