Coordination Chemistry Reviews 257 (2013) 2716–2736 Contents lists available at ScienceDirect Coordination Chemistry Reviews journa l h o me page: www.elsevier.com /lo cate/ccr Review Metal–carboxylato–nucleobase systems: From supramolecular assemblies to 3D porous materials Garikoitz Beobide, Oscar Castillo , Javier Cepeda, Antonio Luque, Sonia Pérez-Yá ˜ nez, Pascual Román, Jintha Thomas-Gipson Departamento de Química Inorgánica, Facultad de Ciencia y Tecnología, Universidad del País Vasco/Euskal Herriko Unibertsitatea, UPV/EHU, Apartado 644, E-48080 Bilbao, Spain Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2716 2. Paddle-wheel shaped secondary building units . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2717 2.1. Composition control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2717 2.2. Magnetic properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2717 2.3. Polymerization strategies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2718 3. [Cu 2 (-adenine) 4 ] secondary building unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2719 3.1. Porous MBioFs based on [Cu 2 (-adenine) 4 ] units . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2720 3.2. Porous supraMBioFs based on [Cu 2 (-adenine) 4 ] units . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2720 4. [Cu 2 (-adenine) 2 (-carboxylato) 2 ] secondary building unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2722 4.1. Porous MBioFs based on [Cu 2 (-adenine) 2 (-carboxylato) 2 ] units . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2722 4.2. Fine tuning of the adsorptive properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2724 4.3. Overtaking gas uptake capacity limited by the crystal structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2726 5. [Cu 2 (-carboxylato) 4 ] secondary building unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2727 6. Other metal–carboxylato–adenine systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2728 6.1. Metal-malonato-adenine discrete systems. Magnetic properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2728 6.2. Metal-oxalato-adenine extended systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2729 6.3. Hybrid systems based on metal-oxalato entities and protonated nuclebases . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2732 7. Summary and perspective . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2734 Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2735 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2735 a r t i c l e i n f o Article history: Received 29 November 2012 Accepted 4 March 2013 Available online 29 March 2013 Keywords: Metal-biomolecule-frameworks Supramolecular porous materials Crystal engineering Porous materials Adsorption properties Magnetic properties a b s t r a c t A complete overview of the preparation of metal–carboxylato–nucleobase architectures that range from supramolecular assemblies to 3D porous materials is reported. The basic building units of these materials consist of metal–nucleobase fragments which link together through coordination bonding or by means of supramolecular assembling among the nucleobases anchored to metal centres. In the case of extended systems based on coordination bonds, the connectivity among the metal centres can be achieved through bridging nucleobases and/or by auxiliary organic linkers such as carboxylate and dicarboxylate anions. The latter bridging mode confers to the nucleobases a greater capacity to involve in molecular recognition processes with other biologically relevant species by means of the establishment of non-covalent inter- actions such as hydrogen bonding and/or stacking among aromatic groups. On the other hand, the geometrical rigidity imposed by several metal–nucleobase fragments and the base pairing interactions through complementary hydrogen bonding, lead to structural restraints that preclude an effective filling of the space, and as a consequence, it favours the growth of tailor-made open-frameworks based either on coordination bonds (MBioFs) or on non-covalent interactions (supraMBioFs). © 2013 Elsevier B.V. All rights reserved. Corresponding author. Tel.: +34 946 015 991. E-mail address: oscar.castillo@ehu.es (O. Castillo). 1. Introduction Metal-organic frameworks (MOFs) encompass an area of chemistry that has experienced awesome growth during the last decades, as indicated by not only the sheer number of research 0010-8545/$ see front matter © 2013 Elsevier B.V. All rights reserved. http://dx.doi.org/10.1016/j.ccr.2013.03.011