Synthesis and single-crystal X-ray characterization of 4,4-functionalized 4′(4-bromophenyl)-2,2′:6′,2-terpyridines

To expand the utility of bis(terpyridine) metal connectivity, the selective symmetrical and unsymmetrical 4,4-functionalization (-CN, -Me, -CO2Me) of 4'-(4-bromophenyl)-2,2':6',2-terpyridines was achieved using the Krohnke synthesis The final substituted 2,2':6',2-terpyridines along with their corresponding intermediates, 4a-c, were recrystallized and characterized by H-1 NMR and C-13 NMR as well as X-ray crystallography; COSY correlations were also conducted to permit definitive proton assignment.