Diverse Topologies in Chiral Divalent Metal Camphorate Coordination Polymers Containing 4,4′-Dipyridylamine

Abstract

Hydrothermal synthesis has afforded six chiral divalent metal coordination polymers containing d-camphorate (d-cmph) and 4,4′-dipyridylamine (dpa) ligands, whose topologies depend largely on metal coordination geometry preference. Both cadmium derivatives {[Cd­(dpa)­(d-cmphH)2(H2O)]·0.875H2O} n (1) and {[Cd­(d-cmph)­(dpa)­(Hdpa)]­ClO4} n (1a) exhibit one-dimensional (1-D) chains with protonated pendant ligands; 1 possesses sinusoidal chains with a “wavelength” of over 67 Å. [Zn2(d-cmph)2(dpa)­(H2O)] n (2) exhibits a two-dimensional (2-D) 3,4-connected binodal net with (53)2(5482) topology. {[Ni­(d-cmph)­(dpa)]·3H2O} n (3) and {[M2(d-cmph)2(dpa)]·H2O} n (M = Co, 4; M = Cu, 5) manifest three-dimensional (3-D) networks. The nickel derivative has an uncommon 2-fold interpenetrated 4-connected 4284 lvt topology, while the isostructural cobalt and copper complexes possess 6-connected pcu topologies based on {M2(OCO)4} paddlewheel dimers. Complexes 1/1a and 2 undergo visible light emission upon ultraviolet excitation. Variable temperature magnetic susceptibility experiments indicate weak (J = −3.6(2) cm–1) and strong (J = –202(5) cm–1) antiferromagnetic coupling for 4 and 5, respectively.

Metal–Organic Frameworks Constructed from d-Camphor Acid: Bifunctional Properties Related to Luminescence Sensing and Liquid-Phase Separation

“…In our effort, which is aimed toward multifunctional MOFs, flexible d -camphor acid ( d -H 2 cam), − rigid 4,4′-bis­(1-imidazolyl)­biphenyl (bimb), and transition-metal centers (Mn 2+ /Co 2+ /Cd 2+ ) were selected to construct new structures with potential applications in luminescence sensing and liquid-phase separation based on the following considerations: (1) the binding between d -H 2 cam and metal centers not only adds flexibility and diversity in the structures but also alters the electronic structures and surface functionalities of the MOFs, which may direct their specific recognition for guest substrates through host–guest interactions; (2) rigid ligand bimb with aromatic π rings may effectively favor intraligand interactions and promote luminescent character. Herein, we present three MOFs, namely, [M 2 ( d -cam) 2 (bimb) 2 ] n ·3.5 n H 2 O (M = Mn for 1 , Co for 2 ) and [Cd 8 ( d -cam) 8 (bimb) 4 ] n ( 3 ), which exhibit structural diversity.…”

Structurally diverse divalent metal pyromellitate coordination polymers with very long spanning dipyridylamide ligands

“…Specific coordination geometric preferences at the divalent metal centers (e.g. square planar, square pyramidal, trigonal bipyramidal, octahedral, pentagonal bipyramidal) can induce significant structural alterations across a series of related coordination polymers [11][12][13], accommodated by the variety of energetically similar carboxylate binding modes. As a result of the enormous parameter space defined by all the possible metal and ligand choices, deliberate tuning of coordination polymer structure and topology has only been achieved in systems of a narrow structural scope [14][15].…”

Binary co-crystals of the active pharmaceutical ingredient 1,4-bis(4-pyridyl)-2,3-diaza-1,3-butadiene and camphoric acid

“…The bioavailability and non-toxic nature of cam makes it a suitable candidate for pharmaceutical preparations. It has been extensively studied and used as a precursor for coordination polymer/MOF synthesis (Smart et al, 2013;Thuery, 2009;Dybtsev et al, 2009;Blake et al, 2012;Chen et al, 2009;Wu et al, 2010). The physiological effects of cam are described and exploited in a few reports (Lima et al, 2012), which essentially indicate the potential of cam as a co-crystal former.…”