Synthesis, structure and magnetic properties of cyclic 3d metal clusters based on N–N single bonds of diacylhydrazine ligand. (15th November 2020) - Tang, Qun
Graphical abstract: The ring dodecanuclear {Co12 } clusters and double cyclic icosanuclear {Mn20 } clusters based on N–N single bonds of diacylhydrazine ligand have been synthesized and characterized structurally. Magnetic studies indicate that these high-nuclearity ring clusters exhibit antiferromagnetic interactions. Highlights: Two cyclic high-nuclearity 3d metal clusters were synthesized. {Co12 } cluster presents a dodecanuclear ring structure consisting of two symmetrical hemicyclic skeletons. {Mn20 } cluster possesses a double cyclic icosanuclear structure consisting of two deca-nuclear ring skeletons. Magnetic studies reveal antiferromagnetic interaction in {Co12 } and {Mn20 } clusters. Abstract: Two cyclic high-nuclearity 3d metal clusters formulated as [Co II 8 Co III 4 (bdsh)4 (Py)12 (MeOH)4 (OAc)4 ]·14CH3 OH·4H2 O ({Co12 } cluster) and [Mn II 4 Mn III 12 Mn IV 4 (bdsh)10 (Py)2 (DMF)8 (H2 O)8 ]·16DMF·2CH3 OH·8H2 O ({Mn20 } cluster), (H6 bdsh = N, N' -bis(2-salicylhydrazide)isophthalohydrazide, Py = pyridine, and DMF = N, N' -dimethylformamide), were synthesized by a conventional solution method. The {Co12 } cluster presents a dodecanuclear ring structure consisting of two symmetrical hemicyclic skeletons bridged with two cobalt ions through the phenolic hydroxyl oxygen atom of H6 bdsh ligand, the hemicyclic skeleton in which five cobalt ions are bridged by four N–N single bonds of diacylhydrazine ligands. The {Mn20 } cluster exhibits a double cyclic structure comprising of two decanuclear ring skeleton bridged with two phenolic hydroxyl oxygen atoms of H6 bdsh ligands, the decanuclear skeleton in which ten manganese ions are bridged by ten N–N single bonds of five H6 bdsh ligands. Magnetic studies reveal the existence of antiferromagnetic interactions in both {Co12 } and {Mn20 } clusters.