Chiral four-fold interpenetrating 2D cadmium networks based on two achiral ligands

Synthesis and structural characterization of a luminescent cadmium(II) complex with bis(4-(1H-imidazole-1-yl)phenyl)amine and 4,4′-sulfonyldibenzoate ligands

A new coordination polymer {[Cd(BIPA)(DCPS)](H2O)} n (1) was constructed with bis(4-(1H-imidazole-1-yl)phenyl)amine and 4,4′-sulfonyldibenzoate ligands. The complex 1 features (BIPA–Cd–BIPA) n and (DCPS–Cd–DCPS) n helical chains in a 3D architecture assembled via hydrogen bonds. A spectroscopic study of complex 1 in the crystalline state showed an intense red-shifted photoluminescence as compared with the ligands BIPA and DCPS2−, which can be attributed to the ligand-to-metal charge transfer (LMCT) transitions.

Selective fluorescent sensing of LMOFs constructed from tri(4-pyridylphenyl)amine ligand

Three new luminescent metal-organic frameworks (LMOFs), [Zn(tppa)(ndc)] _n (1), [Cd(tppa)(oba)] _n (2), [Zn₂(tppa)(bpdc)₂] _n (3) (tppa = tri(4-pyridylphenyl)amine, ndc = 1,4-naphthalenedicarboxylic acid, oba = 4,4'-oxydibenzoic acid, bpdc = 4,4'-biphenyldicarboxylic acid) have been synthesized by solvothermal method. Complexes 1 and 2 are 2-D two-fold interpenetrating structures, aligning into a 3-D structure through C-H⋯π stacking interactions, while 3 is a 5-fold interpenetrating three-dimensional structure. The internal quantum yields (IQYs) of complexes 1-3 are 32.7%, 45.7% and 24.0% (λ _ex = 365 nm), separately. Furthermore, all the complexes show different luminescence signal changes towards aromatic volatile organic compounds (AVOCs). Complex 1 exhibits a high sensitivity in the detection of both Fe³⁺ and Cr³⁺ with large quenching coefficients of K _sv 2.57 × 10⁴ M^-1 and 2.96 × 10⁴ M^-1, respectively. All these results demonstrated potential applications in chemical sensing.

Molecular tectonics: enantiomerically pure chiral crystals based on trans-1,2-cyclohexanediol

Enantiomerically pure trans-1,2-cyclohexanediol ((R,R) or (S,S)) based organic ligands act self-complementary units. In addition, their coordination behavior towards Cd²⁺ cation in the presence of N donor ancillary ligand was investigated.

A new one-dimensional cadmium(II) coordination polymer incorporating 4-[4-(1H-imidazol-1-yl)phenyl]pyridine and 5-hydroxybenzene-1,3-dicarboxylate ligands

The design and synthesis of new organic lgands is important to the rapid development of coordination polymers (CPs). However, CPs based on asymmetric ligands are still rare, mainly because such ligands are usually expensive and more difficult to synthesize. The new asymmetric ligand 4-[4-(1H-imidazol-1-yl)phenyl]pyridine (IPP) has been used to construct the title one-dimensional coordination polymer, catena-poly[[[aqua{4-[4-(1H-imidazol-1-yl-κN(3))phenyl]pyridine}cadmium(II)]-μ-5-hydroxybenzene-1,3-dicarboxylato-κ(3)O(1),O(1'):O(3)] monohydrate], {[Cd(C8H4O5)(C14H11N3)2(H2O)]·H2O}n, under hydrothermal reaction of IPP with Cd(II) in the presence of 5-hydroxyisophthalic acid (5-OH-H2bdc). The Cd(II) cation is coordinated by two N atoms from two distinct IPP ligands, three carboxylate O atoms from two different 5-OH-bdc(2-) dianionic ligands and one water O atom in a distorted octahedral geometry. The cationic [Cd(IPP)2](2+) nodes are linked by 5-OH-bdc(2-) ligands to generate a one-dimensional chain. These chains are extended into a two-dimensional layer structure via O-H...O and O-H...N hydrogen bonds and π-π interactions.