Dy single-molecule magnets from ligands incorporating both amine and acylhydrazine Schiff base groups: the centrosymmetric {Dy} displaying dual magnetic relaxation behaviors.

The novel multidentate chelating ligands N'-(2-pyridylmethylidene)-2-(2-pyridylmethylideneamino)benzohydrazide (Hpphz) and N'-(2-salicylmethylidene)-2-(2-salicylmethylideneamino)benzohydrazide (Hsshz), which incorporate both amine and acylhydrazine Schiff base groups, were synthesized and investigated in Dy coordination chemistry. The reactions of Hpphz and Dy(OAc)·4HO have yielded two {Dy} featuring double OAc bridges: [Dy(Haphz)(OAc)(ROH)] [R = Me (1) and Et (2)], where the Hpphz ligands were in situ hydrolyzed into 2-amino-(2-pyridylmethylideneamino)benzohydrazide ions (Haphz). Besides, the reaction between Hsshz and Dy(NO)·6HO afforded a [Dy(sshz)(μ-OH)(μ-O)(MeOH)]·17.