Topological Diversity of Supramolecular Networks Constructed from Copper(II) Aminoalcohol Blocks and 2,6-Naphthalenedicarboxylate Linkers: Self-Assembly Synthesis, Structural Features, and Magnetic Properties

A series of copper­(II) aminoalcohol derivatives [Cu2(μ-dmea)2­(μ-nda)­(H2O)2]n·2nH2O (1), [Cu2(μ-Hmdea)2­(μ-nda)]n­·2nH2O (2), [Cu2(μ-Hbdea)2­(μ-nda)]n­·2nH2O (3), and [Cu2(H4etda)2­(μ-nda)]­·nda­·4H2O (4) were generated by aqueous medium self-assembly at ∼25 °C from copper­(II) nitrate, various aminoalcohols [N,N′-dimethylethanolamine (Hdmea), N-methyldiethanolamine (H2mdea), N-butyldiethanolamine (H2bdea), or N,N,N′,N′-tetrakis­(2-hydroxyethyl)­ethylenediamine (H4etda) for 1–4, respectively], sodium hydroxide, and 2,6-naphthalenedicarboxylic acid (H2nda). They were isolated as crystalline solids and fully characterized by IR and electron paramagnetic resonance spectroscopy, electrospray ionization mass spectrometry (ESI–MS(±)), thermogravimetric, elemental, and single-crystal X-ray diffraction analyses. The latter revealed that 1–3 are one-dimensional (1D) coordination polymers assembled from dicopper­(II) aminoalcohol blocks and μ-nda linkers, whereas 4 is a discrete zero-dimensional (0D) dimer composed of two [Cu­(H4etda)]2+ fragments interlinked by the μ-nda moiety. In spite of some structural similarities, the main distinctive features of 1–4 arise from the different H-bonding patterns driven by the crystallization H2O molecules, thus giving rise to a further extension of the structures [1D → 3D (1, 2), 1D → 2D (3), or 0D → 3D (4)] into distinct supramolecular networks. Their topological analysis disclosed very complex multinodal nets with unique (1, 2, 4) or rare (3) topologies, which, upon further simplification, furnished a binodal 4,6-connected net with the sqc513 topology in 1, a trinodal 3,4,6-connected net with the 3,4,6L6 topology in 3, and trinodal 3,4,6- or 3,4,8-connected nets with undocumented topologies in 2 and 4, respectively. The magnetic susceptibility studies of 1–3 indicate a strong antiferromagnetic coupling between the CuII atoms through the μ-alkoxo bridges [J = −470(2), −100(2), and −590(1) cm–1, respectively], which was described by the Bleaney–Bowers dinuclear model. In contrast, 4 is devoid of any significant magnetic interaction within the dicopper­(II) units.