Great efforts have been made on the design and construction of supramolecular coordination polymers not only due to their fascinating structural features but also their potential in conventional and emerging applications.1−8 Metal complexes of azamacrocycles along with multidentate ligand linkers have been considered as good building blocks for the formation of supramolecular coordination polymers.9 During the formation of final structures, intermolecular forces such as hydrogen bonds, π-π interactions, and CH-π interactions, etc are frequently involved.10,11 Rational design and the synthetic strategy of supramolecular coordination polymers via a self-assembly process largely depend on the selection of metal ion connectors and bridging ligand linkers. Thus, the metal complex of tetraazamacrocycle L which bears trans/cisfused cyclohexane rings on a cyclam backbone could potentially extend its structure to the axial direction of metal ion by the coordination of bridging ligands, resulting in the formation of 1D coordination polymer. In addition, the macrocycle L and its zinc(II) complex attracted attention due to their revealing anti-HIV activity.12 Rigid organic linkers, in particular, aromatic polycarboxylates have widely been employed to generate coordination polymers with macrocyclic metal ion connectors.13,14 In contrast, flexible organic building blocks have been far less exploited as their backbone flexibility makes the resulting coordination polymers difficult to predict and control. However, the flexibility of organic linkers is all the better preferred by researchers to design and construct a new class of coordination polymers in spite of the above mentioned demerits.15,16 Recent articles about the development of flexible ligands in the realm of coordination polymers substantiate the importance of flexible ligands.17,18 An aromatic dicarboxylic acid, bpdcH 2 (bpdc = 4,4'-biphenyl dicarboxylate), may be a good candidate as an organic building block for the construction of supramolecular coordination polymer due to its coordinating ability and the possibility of intermolecular interactions arising between the aromatic rings. Though the bpdcH 2 molecule contains rigid aromatic rings, it also exhibits flexibility via rotation about a carbon-carbon single bond. Another best known flexible ligand is 1,4-chdcH 2 (1,4-chdc = 1,4-cyclohexane dicarboxylate) which can adopt three different conformations, i.e. e,e-trans-1,4-chdcH 2 , a,e-cis-1,4-chdcH 2 and a,a-trans-chdcH 2 . The 1,4-chdcH 2 molecule can show versatile coordination modes to metal ions depending on the degree of deprotonation and participate in intermolecular interactions by acting as hydrogen bond donors and/or acceptors. With the purpose to try and find out coordination polymers having fascinating structural features, we employed the macrocyclic zinc(II) complex as a metal ion connector, and dicarboxylates bpdc and e,e-trans-1,4-chdc as bridging ligand linkers (Scheme 1). From the self-assembly processes of an appropriate combination of metal ion ...
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