The synthesis of three new Cu, Cu and Cu clusters via the use of a semi-flexible aminotriazine-based bis-methylpyridine ligand.

The synthesis of three new polynuclear Cu, Cu and Cu clusters has been achieved using a semi-flexible aminotriazine-based bis-methylpyridine ligand, N,N-dibenzyl-N,N-di(pyridylmethyl)-1,3,5-triazine-2,4,6-triamine (Hdpmta). The reaction of Cu(ClO)·6HO with Hdpmta in PrOH afforded the complex Cu(OH)(Hdpmta)(ClO)(HO)·EtO·5PrOH (1). A similar reaction of Cu(ClO)·6HO and Hdpmta in the presence of PhCONa in PrOH/CHCl gave the complex Cu(OH)(OCPh)(Hdpmta)(ClO)(PrOH)·2CHCl·2PrOH (2). The complex CuO(OH)(Hdpmta)(dpmta)(OCMe)·2MeCN (3) was produced from the reaction of [Cu(OCMe)]·2HO with Hdpmta and NaClO in MeCN/CHCl. Single-crystal X-ray diffraction measurements were carried out on these complexes. The Cu cluster of 1 consisted of a planar [Cu(μ-OH)] core in a rectangle-like arrangement. The Cu cluster of 2 represented a [Cu(μ-OH)(μ-OH)] core infusion of two [Cu(OH)] butterfly subunits. Complex 3 possesses a bent [Cu(μ-O)(μ-OH)] core structure, in which a central [Cu(μ-O)] square planar moiety was fused with two butterfly-like [Cu(μ-O)(μ-OH)] subunits. The magnetic properties of these three complexes were characterized by the measurements of variable-temperature and field magnetic susceptibility. The magnetic analysis showed that a strong antiferromagnetic interaction was mediated between Cu(ii) ions by the single OH bridge in 1 and resulted a S = 3/2 spin ground state. In complex 2, both intramolecular antiferro- and ferromagnetic interactions were dominated between Cu(ii) ions resulting a spin ground state of S = 2. Indeed, complex 3 displayed an overall antiferromagnetic coupling.