Large size anion binding with iron(ii) complexes of a 5,5′-disubstituted-2,2′-bipyridine ligandElectronic supplementary information (ESI) available: synthesis and characterization of 1a–c. All new compounds were characterised by CHN, 1H NMR, and ESI-MS. See http://www.rsc.org/suppdata/cc/b2/b211616b/

Abstract

Three 5,5'-substituted 2,2'-bipyridyl ligands around a metal atom form two clefts which can encapsulate sulfate, perchlorate, or nitrate anions.