Synthesis, crystal structure, and theoretical studies of a macrocyclic silver(I) complex of imino-pyridyl Schiff base ligand

The synthesis and characterization of an imino-pyridyl ligand N,N'-(butane-1,4-diyl)bis(1-(pyridin-2-yl)methanimine) (L) and its Ag(I)ClO4 complex (I) by various spectroscopic techniques and elemental analyses is presented in this study. X-ray single crystal structure of complex I revealed that in complex I, each Ag(I) ion is tetra coordinated with two pyridine N-atoms and two imine N-atoms of the ligand L, forming a macrocyclic dimeric Ag(I) grid. In the macrocyclic dimer complex I, Ag-Ag separation along the chain is 5.318 Å. The Ag-Npy average distance is 2.396 Å and that of the Ag-Nim is 2.257 Å. The macrocyclic dimer complex I is supramolecularly arranged by π-stacking interactions. Computational, Hirshfeld surface analysis and photophysical studies on ligand L and complex I have also been performed. Crystal data for C32H36Ag2Cl2N8O8 (M =947.33 g/mol): Triclinic, space group P-1 (no. 2), a = 9.1714(12) Å, b = 10.4373(14) Å, c = 10.8297(14) Å, α = 112.317(3)°, β = 91.391(3)°, γ = 92.353(3)°, V = 957.3(2) Å3, Z = 1, T = 293.15 K, μ(MoKα) = 1.220 mm-1, Dcalc = 1.643 g/cm3, 10248 reflections measured (4.07° ≤ 2Θ ≤ 53.098°), 3966 unique (Rint = 0.0280, Rsigma = 0.0331) which were used in all calculations. The final R1 was 0.0722 (I > 2σ(I)) and wR2 was 0.2229 (all data).

Three Zn(ii) coordination polymers constructed with a new amide-thiophene-derived bis-pyridyl ligand as ultrasensitive luminescent sensors for Hg(ii) and purines

A new amide-thiophene-derived ligand (4-bpft) was designed and used to construct three LCPs 1–3, which could detect Hg(ii), adenine, and guanine.

Various carboxylates induced eight Zn(ii)/Cd(ii) coordination polymers with fluorescence sensing activities for Fe(iii), Cr(vi) and oxytetracycline

Eight new Zn(ii)/Cd(ii) coordination polymers constructed from a naphthalene-amide-pyridyl ligand and various carboxylates were synthesized and characterized, which show multifunctional fluorescence responses for cations, anions and antibiotics.

Self-assembly of a water-soluble endohedrally functionalized coordination cage including polar guests

A tetra-cationic calix[4]pyrrole tetra-pyridyl ligand self-assembles into a water-soluble Pd(ii)-cage featuring two endohedral polar binding sites. The Pd(ii)-cage encapsulates pyridyl N-oxide and aliphatic formamide guests in water.

Imino-pyridyl and PPh3 mixed ligand complexes of Cu(I)X (X: I, Br, and Cl): Synthesis, structure, DFT and Hirshfeld surface studies

Three new halide bridged copper(I)complexes [Cu2(µ-L)(µ-X)2)(PPh3)2]n {X: I (1), Br (2) and Cl (3)} have been synthesized by the reaction of Cu(I)X (X: I, Br and Cl) with PPh3 and the polydentate imino-pyridyl ligand L. Interestingly, copper(I) forms coordination polymers with the ligand L and the co-ligand PPh3. These complexes 1, 2 and 3 have been characterized by elemental analysis, IR, UV-Vis, and NMR spectroscopy. The crystal structure of the complex 2 has been determined by single-crystal X-ray analysis. Crystal data for complex 2: triclinic, space group P-1 (no. 2), a = 9.471(10) Å, b = 11.043(11) Å, c = 13.215(18) Å, α = 65.853(18)°, β = 69.94(2)°, γ = 67.350(14)°, V = 1135(2) Å3, Z = 2, T = 296.15 K, μ(MoKα) = 2.806 mm-1, Dcalc = 1.535 g/cm3, 4059 reflections measured (3.462° ≤ 2Θ ≤ 44.818°), 2639 unique (Rint = 0.0637, Rsigma = 0.1621) which were used in all calculations. The final R1 was 0.0700 (I > 2σ(I)) and wR2 was 0.2207 (all data). Hirshfeld surface analysis of the complex 2 showed H···H, N···H and Br···H interactions of 55.9, 14.4 and 4.1%, respectively. MEP of ligand L reflects the whole molecule is reddish yellow in color because of equally distributed electron density over the molecule. For this reason, the ligand is supramolecularly arranged via -{CuI2-µ-X2} rhomboid core in the complex 2. The ligand L is non-emissive at room temperature in dichloromethane, whereas the complexes 1, 2 and 3 are photoluminescent. DFT and Hirshfeld surface studies have also been performed for complex 2.