Syntheses, structures and catecholase activities of homo‐ and hetero‐trinuclear cobalt(II) complexes constructed from an acyclic naphthalenediol‐based bis(Salamo)‐type ligand

A series of homo‐ and hetero‐trinuclear cobalt(II) complexes [Co 3 (L)(OAc) 2 (CH 3 CH 2 OH)(H 2 O)] ( 1 ), [Co 2 Ba(L)(OAc) 2 ] ( 2 ) and [Co 2 Ca(L)(OAc) 2 ]·CHCl 3 ( 3 ), containing an acyclic naphthalenediol‐based ligand H 4 L were synthesized. All the three complexes were characterized by elemental analyses, IR, UV – vis spectra and single crystal X‐ray diffraction analyses. Comparative studies of the structures and spectroscopic properties are carried out on these complexes. All of the complexes show catechol oxidase activities in MeCN. Using UV – vis spectroscopy, we monitored the aerial oxidation of 3,5‐di‐ tert ‐butylcatechol (3,5‐DTBCH 2 ) to 3,5‐di‐ tert ‐butylquinone (3,5‐DTBQ), which confirms the essential role of these complexes in enhancing the catalytic reaction.