Dicarboxylate-Induced Structural Diversity of Luminescent Zn(II)/Cd(II) Metal-Organic Frameworks Based on the 2,5-Bis(4-pyridyl)thiazolo[5,4- d ]thiazole Ligand: Dicarboxylate-Induced Structural Diversity of Luminescent Zn(II)/Cd(II) Metal-Organic Frameworks Based on the 2,5-Bis(4-pyridyl)thiazolo[5,4-d]thiazol

Coordination Polymers from Biphenyl-Dicarboxylate Linkers: Synthesis, Structural Diversity, Interpenetration, and Catalytic Properties

The present work explores two biphenyl-dicarboxylate linkers, 3,3'-dihydroxy-(1,1'-biphenyl)-4,4'-dicarboxylic (H₄L₁) and 4,4'-dihydroxy-(1,1'-biphenyl)-3,3'-dicarboxylic (H₄L₂) acids, in hydrothermal generation of nine new compounds formulated as [Co₂(μ₂-H₂L₁)₂(phen)₂(H₂O)₄] (1), [Mn₂(μ₄-H₂L₁)₂(phen)₂]_n·4nH₂O (2), [Zn(μ₂-H₂L₁)(2,2'-bipy)(H₂O)]_n (3), [Cd(μ₂-H₂L₁) (2,2'-bipy)(H₂O)]_n (4), [Mn₂(μ₂-H₂L₁)(μ₄-H₂L₁)(μ₂-4,4'-bipy)₂]_n·4nH₂O (5), [Zn(μ₂-H₂L₁)(μ₂-4,4'-bipy)]_n (6), [Zn(μ₂-H₂L₂)(phen)]_n (7), [Cd(μ₃-H₂L₂)(phen)]_n (8), and [Cu(μ₂-H₂L₂) (μ₂-4,4'-bipy)(H₂O)]_n (9). These coordination polymers (CPs) were generated by reacting a metal(II) chloride, a H₄L₁ or H₄L₂ linker, and a crystallization mediator such as 2,2'-bipy (2,2'-bipyridine), 4,4'-bipy (4,4'-bipyridine), or phen (1,10-phenanthroline). The structural types of 1-9 range from molecular dimers (1) to one-dimensional (3, 4, 7) and two-dimensional (8, 9) CPs as well as three-dimensional metal-organic frameworks (2, 5, 6). Their structural, topological, and interpenetration features were underlined, including an identification of unique two- and fivefold 3D + 3D interpenetrated nets in 5 and 6. Phase purity, thermal and luminescence behavior, as well as catalytic activity of the synthesized products were investigated. Particularly, a Zn(II)-based CP 3 acts as an effective and recyclable heterogeneous catalyst for Henry reaction between a model substrate (4-nitrobenzaldehyde) and nitroethane to give β-nitro alcohol products. For this reaction, various parameters were optimized, followed by the investigation of the substrate scope. By reporting nine new compounds and their structural traits and functional properties, the present work further outspreads a family of CPs constructed from the biphenyl-dicarboxylate H₄L₁ and H₄L₂ linkers.

The crystal structure of 2,5-bis(3,5-dimethylphenyl)thiazolo[5,4-d]thiazole, C20H18N2S2

C20H18N2S2, monoclinic, P21/n (no. 14), a = 7.92140(10) Å, b = 6.08080(10) Å, c = 17.8091(3) Å, β = 90.592(2)°, V = 857.79(2) Å3, Z = 4, R gt(F) = 0.0382, wR ref(F 2) = 0.1051, T = 149.99(10) K.

CCDC no.: 2085420

A new thermostable Cu(II) coordination polymer: photocatalytic activity and application values on diabetes

A Cu(II) coordination polymer with the composition of [Cu₂(L)₂(4,4'-bipy)₂]_n·2 n(ClO₄) (1, HL = 4-methyl-L-phenylalanine and 4,4'-bipy is 4,4'-bipyridine), was successfully obtained by the reaction of the mixed ligand of HL and 4,4'-bipy with Cu(ClO₄)₂ · 6H₂O under solvothermal condition. The as-synthesized compound not only has high thermal stability until 275°C but also excellent photocatalytic activity for the methyl blue solution degradation under the irradiation of ultraviolet light. Furthermore, the compound's treatment activity on the diabetes was determined and its relevant mechanism was also studied. The cytotoxicity or hemolysis toxicity (HC50) of the synthesized compound was also evaluated in this research.

Coordination polymers from an unexplored biphenyl-tricarboxylate linker: hydrothermal synthesis, structural traits and catalytic cyanosilylation

3,2′,4′-Biphenyl-tricarboxylic acid (H₃bta) was used as a versatile linker for preparing a new series of metal(ii) (Zn, Ni, and Cd) coordination polymers and complexes with notable structural, luminescence and catalytic features.

Coordination Polymers Based on Highly Emissive Ligands: Synthesis and Functional Properties

Coordination polymers are constructed from metal ions and bridging ligands, linking them into solid-state structures extending in one (1D), two (2D) or three dimensions (3D). Two- and three-dimensional coordination polymers with potential voids are often referred to as metal-organic frameworks (MOFs) or porous coordination polymers. Luminescence is an important property of coordination polymers, often playing a key role in their applications. Photophysical properties of the coordination polymers can be associated with intraligand, metal-centered, guest-centered, metal-to-ligand and ligand-to-metal electron transitions. In recent years, a rapid growth of publications devoted to luminescent or fluorescent coordination polymers can be observed. In this review the use of fluorescent ligands, namely, 4,4'-stilbenedicarboxylic acid, 1,3,4-oxadiazole, thiazole, 2,1,3-benzothiadiazole, terpyridine and carbazole derivatives, naphthalene diimides, 4,4',4''-nitrilotribenzoic acid, ruthenium(II) and iridium(III) complexes, boron-dipyrromethene (BODIPY) derivatives, porphyrins, for the construction of coordination polymers are surveyed. Applications of such coordination polymers based on their photophysical properties will be discussed. The review covers the literature published before April 2020.

Synthesis, Crystal Structures and Luminescence Properties of Three New Cadmium 3D Coordination Polymers

The new rigid planar ligand 2,5-bis(3-(pyridine-4-yl)phenyl)thiazolo[5,4-d]thiazole (BPPT) has been synthesized, which is an excellent building block for assembling coordination polymer. Under solvothermal reaction conditions, cadmium ion with BPPT in the presence of various carboxylic acids including (1,1′-biphenyl)-4,4′-dicarboxylic acid (BPDC), isophthalic acid (IP), and benzene-1,3,5-tricarboxylic acid (BTC) gave rise to three coordination complexes, viz, [Cd(BPPT)(BPDA)](BPPT)n (1), [Cd(BPPT) (IP)] (CH₃OH) (2), and [Cd₃(BPPT)₃(BTC)₂(H₂O)₂] (3). The structures of 1, 2, and 3 were characterized by single crystal X-ray diffraction. The IR spectra as well as thermogravimetric and luminescence properties were also investigated. Complex 1 is a two-dimensional (2D) network and further stretched to a 3D supramolecular structure through π–π stacking interaction. The complexes 2 and 3 show 3D framework. The complexes 1, 2, and 3 exhibited luminescence property at room temperature.

H-Bonded and metal(ii)-organic architectures assembled from an unexplored aromatic tricarboxylic acid: structural variety and functional properties

This study reports the application of an aromatic tricarboxylic acid, 2,5-di(4-carboxylphenyl)nicotinic acid (H3dcna) as a versatile and unexplored organic building block for assembling a new series of metal(ii) (M = Co, Ni, Zn, Fe, and Mn) complexes and coordination polymers, namely [M(Hdcna)(phen)2(H2O)]·H2O (M = Co (1), Ni (2)), [Zn(μ-Hdcna)(phen)]n (3), [Co(μ-Hdcna)(bipy)(H2O)2]n·nH2O (4), [Zn2(μ-Hdcna)2(bipy)2(H2O)4]·6H2O (5), [Zn(μ3-Hdcna)(H2biim)]n (6), [Ni2(Hdcna)2(μ-bpb)(bpb)2(H2O)4] (7), [Fe(μ4-Hdcna)(μ-H2O)]n·nH2O (8), and [Mn3(μ5-dcna)2(bipy)2(H2O)2]n·2nH2O (9). Such a diversity of products was hydrothermally prepared from the corresponding metal(ii) salts, H3dcna as a principal multifunctional ligand, and N-donor mediators of crystallization (1,10-phenanthroline, phen; 2,2'-bipyridine, bipy; 2,2'-biimidazole, H2biim; or 1,4-bis(pyrid-4-yl)benzene, bpb). The obtained products 1-9 were fully characterized by standard methods (elemental analysis, FTIR, TGA, PXRD) and the structures were established by single-crystal X-ray diffraction. These vary from the discrete monomers (1, 2) and dimers (5, 7) to the 1D (3, 4, 6) and 2D (8, 9) coordination polymers (CPs). Structural and topological characteristics of hydrogen-bonded or metal-organic architectures in 1-9 were highlighted, revealing that their structural multiplicity depends on the type of metal(ii) source and crystallization mediator. Thermal stability as well as luminescent, magnetic, or catalytic properties were explored for selected compounds. In particular, the zinc(ii) derivatives 3, 5, and 6 were applied as efficient heterogeneous catalysts for the cyanosilylation of aldehydes with trimethylsilyl cyanide at room temperature. The catalytic reactions were optimized by tuning the different reaction parameters (solvent composition, time, catalyst loading) and the substrate scope was also explored. Compound 5 revealed superior catalytic activity leading to up to 75% product yields, while maintaining its original performance upon recycling for at least four reaction cycles. Finally, the obtained herein products represent the unique examples of coordination compounds derived from H3dcna, thus opening up the use of this multifunctional tricarboxylic acid for generating complexes and coordination polymers with interesting structures and functional properties.

Thiazole- and Thiadiazole-Based Metal–Organic Frameworks and Coordination Polymers for Luminescent Applications

This mini-review focuses on the 2015–2019 literature survey of thiazole- and thiadiazole-containing Metal–Organic Frameworks (MOFs) and Coordination Polymers (CPs) exploited in the applicative field of luminescent sensing.