New Tetracopper(II) Cubane Cores Driven by a Diamino Alcohol: Self- assembly Synthesis, Structural and Topological Features, and Magnetic and Catalytic Oxidation Properties Sara S. P. Dias, † Marina V. Kirillova, † Va ̂ nia Andre ́ , † Julia Klak, ‡ and Alexander M. Kirillov* ,† † Centro de Química Estrutural, Complexo I, Instituto Superior Te ́ cnico, Universidade de Lisboa, Avenida Rovisco Pais, 1049-001 Lisbon, Portugal ‡ Faculty of Chemistry, University of Wroclaw, ul. F. Joliot-Curie 14, 50-383 Wroclaw, Poland * S Supporting Information ABSTRACT: Two new coordination compounds with tetracopper(II) cores, namely, a 1D coordination polymer, [Cu 4 (μ 4 -H 2 edte)(μ 5 -H 2 edte)(sal) 2 ] n · 10nH 2 O(1), and a discrete 0D tetramer, [Cu 4 (μ 4 -Hedte) 2 (Hpmal) 2 (H 2 O)]· 7.5H 2 O(2), were easily self-assembled from aqueous solutions of copper(II) nitrate, N,N,N′,N′-tetrakis(2-hydroxyethyl)ethylenediamine (H 4 edte), salicylic acid (H 2 sal), or phenylmalonic acid (H 2 pma). The obtained compounds were characterized by IR and electron paramagnetic resonance spectroscopy, thermogravimetric and elemental analysis, and single-crystal X-ray diffraction. In addition to different dimensionalities, their structures reveal distinct single- open [Cu 4 (μ 2 -O)(μ 3 -O) 3 ] (in 1) or double-open [Cu 4 (μ 2 -O) 2 (μ 3 -O) 2 ] (in 2) cubane cores with 3M4-1 topology. In crystal structures, numerous crystallization water molecules are arranged into the intricate infinite 1D {(H 2 O) 18 } n water tapes (in 1) or discrete (H 2 O) 9 clusters (in 2) that participate in multiple hydrogen-bonding interactions with the metal-organic hosts, thus extending the overall structures into very complex 3D supramolecular networks. After simplification, their topological analysis revealed the binodal 6,10- or 6,8-connected underlying 3D nets with unique or rare 6,8T2 topology in 1 and 2, respectively. The magnetic properties of 1 and 2 were investigated in the 1.8-300 K temperature range, indicating overall antiferromagnetic interactions between the adjacent Cu II ions within the [Cu 4 O 4 ] cores. The obtained compounds also act as bioinspired precatalysts for mild homogeneous oxidation, by aqueous hydrogen peroxide at 50 °C in an acidic MeCN/H 2 O medium, of various cyclic and linear C 5 -C 8 alkanes to the corresponding alcohols and ketones. Overall product yields of up to 21% (based on alkane) were achieved, and the effects of various reaction parameters were studied. ■ INTRODUCTION Amino alcohols are recognized N,O building blocks for the design of coordination compounds that include a diversity of discrete multinuclear metal complexes, clusters, and molecular wheels, as well as various coordination polymers and metal- organic frameworks. 1-3 Owing to their different functional properties, these amino alcohol driven compounds have found notable applications in areas ranging from molecular magnetism and catalysis to supramolecular chemistry and crystal engineer- ing. 3-7 Among the variety of simple amino alcohols (e.g., N,N- dimethylethanolamine, diethanolamine, and triethanolamine), N,N,N′,N′-tetrakis(2-hydroxyethyl)ethylenediamine (H 4 edte) represents an interesting multidentate diamine with four ethyl alcohol groups. However, in spite of its low cost and commercial availability, water solubility and stability, potential coordination flexibility and versatility, the application of H 4 edte toward the design of multinuclear metal complexes and, in particular, coordination polymers has remained underex- plored. 1,6,7 Although some notable examples of high-nuclearity Mn 6 and Fe 7 clusters driven by H 4 edte have been reported, the coordination chemistry of H 4 edte toward Cu is still limited to single mono- or dicopper(II) complexes, 5a,8 as attested by a search of the Cambridge Structural Database. 1 Bearing these points in mind and following our general interest in the exploration of various amino alcohol building blocks for the generation, by a simple aqueous medium self- assembly method, of diverse functional multicopper(II) complexes and coordination polymers, 3,5 the principal objectives of the current work consisted of (i) opening up the application of H 4 edte for the preparation of new discrete and polymeric multicopper(II) derivatives, (ii) identifying their structural and topological features, and (iii) studying their magnetic and catalytic behavior. Hence, we report herein the aqueous medium self-assembly generation, full characterization, crystal structures, topological analysis, and magnetic and oxidation catalytic properties of two Received: January 7, 2015 Published: May 14, 2015 Article pubs.acs.org/IC © 2015 American Chemical Society 5204 DOI: 10.1021/acs.inorgchem.5b00048 Inorg. Chem. 2015, 54, 5204-5212