Structures of [Co(II)(L)(NO3)(HOCH3)n]BPh4 (n = 4, 5) complexes (L = cis,cis-1,3,5-triaminocyclohexane-based ligand): structural ‘snapshots’ of anion binding to a metal centre

The crystal structures of [Co(II)(L)(NO3)(HOCH3)n]BPh4 {L = cis,cis-1,3,5-tri[(4-tert-butylphenyl)propenylideneamino]cyclohexane} complexes demonstrate the role of solvent molecules in the stabilisation of anions withina solvated cavity: the structures can be comparedwith bicarbonate binding in the active site of carbonic anhydrase.