Functionalized Adamantane Tectons Used in the Design of Mixed-Ligand Copper(II) 1,2,4-Triazolyl/Carboxylate Metal–Organic Frameworks

Adamantane-Functionalized Phthalimide Scaffold: Pathways to Supramolecular Interactions and Drug Discovery

Herein, the synthesis of a novel adamantanyl-functionalized phthalimide scaffold is demonstrated. The novel compound could be used as a precursor for various synthetic pathways owing to the generic use of adamantane substituents as the driving force for supramolecular interactions with macrocycles and N-substituted phthalimide derivatives as a core structure in numerous drugs. The adamantanyl-functionalized phthalimide scaffold contains bromide groups on the C4 and C5 positions of the benzene ring, effectively allowing further facile modifications of the scaffold. The structure was fully characterized including single-crystal X-ray crystallography. The crystal structure shows an adamantane moiety at an angle of 115.57(7)° to the phthalimide core, hence sterically freeing the adamantane unit for host–guest interactions.

Synthesis, Crystal Structure, and Luminescence of Cadmium(II) and Silver(I) Coordination Polymers Based on 1,3-Bis(1,2,4-triazol-1-yl)adamantane

Coordination polymers with a new rigid ligand 1,3-bis(1,2,4-triazol-1-yl)adamantane (L) were prepared by its reaction with cadmium(II) or silver(I) nitrates. Crystal structure of the coordination polymers was determined using single-crystal X-ray diffraction analysis. Silver formed two-dimensional coordination polymer [Ag(L)NO₃]_n, in which metal ions are linked by 1,3-bis(1,2,4-triazol-1-yl)adamantane ligands, coordinated by nitrogen atoms at positions 2 and 4 of 1,2,4-triazole rings. Layers of the coordination polymer consist of rare 18- and 30-membered {Ag₂L₂} and {Ag₄L₄} metallocycles. Cadmium(II) nitrate formed two kinds of one-dimensional coordination polymers depending on the metal-to-ligand ratio used in the synthesis. Coordination polymer [Cd(L)₂(NO₃)₂]_n was obtained in case of a 1:2 M:L ratio, while for M:L = 2:1 product {[Cd(L)(NO₃)₂(CH₃OH)]·0.5CH₃OH}_n was isolated. All coordination polymers demonstrated ligand-centered emission near 450 nm upon excitation at 370 nm.

New Coordination Polymers of Zinc(II), Copper(II) and Cadmium(II) with 1,3-Bis(1,2,4-triazol-4-yl)adamantane

The new coordination polymers (CPs) [Zn(tr2ad)Cl2]n, {[Cu(tr2ad)Cl]Cl∙4H2O}n, [Cd2(tr2ad)Cl4]n, {[Cu(tr2ad)(NO3)](NO3)}n and {[Cd(tr2ad)(NO3)](NO3)∙H2O}n were obtained in the form of air- and moisture-stable microcrystalline powders by the solvothermal reactions of zinc(II), copper(II) and cadmium(II) chlorides or nitrates with the ligand 1,3-bis(1,2,4-triazol-4-yl)adamantane (tr2ad). Investigation of the thermal behaviour assessed the thermal stability of these CPs, with [Cd2(tr2ad)Cl4]n starting to decompose only around 365 °C. As retrieved by powder X-ray diffraction, while [Zn(tr2ad)Cl2]n features 1-D chains along which the metal centre shows a tetrahedral geometry and the spacer is exo-bidentate, the other CPs contain 2-D double-layers in which the metal ions possess an octahedral stereochemistry and the linker is exo-tetradentate. A comparative structural analysis involving known coordination compounds containing the tr2ad ligand enabled us to disclose (i) the versatility of the ligand, as far as the coordination modes are concerned; (ii) the variability in crystal structure dimensionality, ranging from 1-D to 3-D; (iii) the fact that, to the best of our knowledge, [Zn(tr2ad)Cl2]n is the first ZnII-based CP containing the tr2ad spacer.

Facile Synthesis of 3-(Azol-1-yl)-1-adamantanecarboxylic Acids-New Bifunctional Angle-Shaped Building Blocks for Coordination Polymers

For the first time, orthogonally substituted azole-carboxylate adamantane ligands were synthesized and used for preparation of coordination polymers. The angle-shaped ligands were prepared by the reaction of 1-adamantanecarboxylic acid and azoles (1H-1,2,4-triazole, 3-methyl-1H-1,2,4-triazole, 3,5-dimethyl-1H-1,2,4-triazole, 1H-tetrazole, 5-methyl-1H-tetrazole) in concentrated sulfuric acid. Variation of the solvent and substituents in azole rings allowed to prepare both 1D and 2D copper(II) and nickel(II) coordination polymers, [Cu₂(trzadc)₄(H₂O)_0.7]∙DMF∙0.3H₂O, [Cu(trzadc)₂(MeOH)]∙MeOH, [Ni(trzadc)₂(MeOH)₂] and [Cu₂(mtrzadc)₃(MeOH)]⁺NO₃^– (trzadc-3-(1,2,4-triazol-1-yl)-adamantane-1-carboxylic acid; mtrzadc-3-(3-methyl-1,2,4-triazol-1-yl)-adamantane-1-carboxylic acid) which were structurally characterized by single crystal X-ray diffraction. Complex [Cu(trzadc)₂(MeOH)]∙MeOH was shown to act as a catalyst in the Chan-Evans-Lam arylation reaction.

A three-dimensional Cd(ii) metal–organic framework: a bifunctional luminescence sensor for benzaldehyde and Fe2+ ions

A three-dimensional Cd(ii) MOF has been constructed. It is (3,6)-connected net showing rtl topology. In addition, it is also a bifunctional luminescence sensor for benzaldehyde and Fe²⁺ ions.

Crystal structure of poly[diaqua-(μ2-4,4′-bipyridine-κ2 N:N′)manganese(II)] bis(4-chlorobenzenesulfonate) – 4,4′-bipyridine – water (1/1/2) C42H40Cl2MnN6O10S2

C42H40Cl2MnN6O10S2, monoclinic, C2/c (no. 15), a = 16.822(14) Å, b = 11.552(9) Å, c = 22.021(17) Å, β = 91.920(13)°, V = 4277(6) Å3, Z = 4, R gt(F) = 0.0641, wR ref(F 2) = 0.1654, T = 296 K.

Crystal structure of poly-[diaqua-bis(μ-4,4′-bipyridine-κ2 N:N′)cobalt(II)] bis(4-chlorobenzenesulfonate) – 4,4′-bipyridine – water (1/1/2), C42H40Cl2CoN6O10S2

C42H40Cl2CoN6O10S2, monoclinic, C2/c, a = 17.447(6) Å, b = 11.467(4) Å, c = 22.691(4) Å, β = 108.31(5)°, V = 4310(2) Å3, Z = 4, R gt(F) = 0.0341, wR ref(F 2) = 0.0921, T = 296 K.

A series of Cd(ii) coordination polymers based on flexible bis(triazole) and multicarboxylate ligands: topological diversity, entanglement and properties

Eight Cd(ii) coordination polymers with diverse topologies based on 1,4-bis(1,2,4-triazol-4-ylmethyl)benzene and multicarboxylate ligands were synthesized and characterized. The 3D topologies of 1, 2 and 3 are unprecedented.

Photoactive and Physical Properties of an Azobenzene-Containing Coordination Framework

A new three-dimensional coordination framework, [Zn4(tbazip)3(bpe)2(OH)2]·bpe·{solvent} (where bpe = 1,2-di(4-pyridyl)ethene) containing the novel photoactive ligand tbazip (tbazip = 5-((4-tert-butyl)phenylazo)isophthalic acid) has been synthesised and crystallographically characterised. The photoactivity of discrete tbazip was investigated and compared with its photoactivity while incorporated within the framework. The effect of isomerisation of the incorporated azobenzene on the chemical and physical properties of the framework were investigated using UV-vis and Raman spectroscopies. The framework is porous only to hydrogen gas at 77 K, but displayed an appreciable uptake for CO2 at 195 K.

A series of transition metal coordination polymers based on a rigid bi-functional carboxylate–triazolate tecton

By utilizing a pre-designed bi-functional ligand, five new transition-metal-based coordination polymers have been constructed and structurally characterized, along with their luminescence or magnetic properties.

Three Cluster Organic Frameworks Constructed from Tetranuclear Cluster Units: Structure and Properties

By treating a semirigid 5-oxyacetate isophthalic acid (H₃ OAIP) ligand with MnSO₄ /CoSO₄ /CdSO₄ under solvothermal conditions, three isostructural cluster organic frameworks, [M₂ (OH)(OAIP)(DMA)]⋅H₂ O (M=Mn²⁺ (1), Co²⁺ (2), Cd²⁺ (3); DMA=N,N'-dimethylacetamide) were constructed. The three complexes contain novel eight-connected tetranuclear M₄ (OH)₂ (COO)₆ (OCH₂ COO)₂ clusters with the unique hexagonal bipyramidal configuration, which are extended by four-connected OAIP linkers to form an uncommon (4,8)-connected alb-4,8-Cmce topology based on (3,6)-connected kgd sublayers. Both 1 and 2 showed significant antiferromagnetic interactions between the intracluster metal ions, whereas 3 revealed strong blue photoluminescence.

A new strategy to obtain tetranuclear cobalt(ii) metal–organic frameworks based on the [Co4(μ3-OH)2] cluster: synthesis, structures and properties

Three MOFs based on [Co₄(μ₃-OH)₂] with 4-, 6- and 8-connected frameworks exhibit antiferromagnetic interactions and are good photocatalysts.

Structure-induced catalysis enhancement of Cu-amino catalysts for rapidly selective oxidation of sulfides in the presence of H2O2

A Cu-amino coordination polymer promotes rapid sulfoxidation of benzyl phenyl sulfide toward the sulfoxide with high conversion and selectivity.

Mixed-ligand hydroxocopper(ii)/pyridazine clusters embedded into 3D framework lattices

Three types of polynuclear Cu(ii) clusters rely on the compatibility of short-distance hydroxo-, carboxylato and pyridazine bridges and are applicable for the construction of 3D MOF structures.

Assembly of a series of d10 coordination polymers of pamoic acid through a mixed-ligand synthetic strategy: syntheses, structures and fluorescence properties

Eight fluorescent coordination compounds were obtained based on H₂PA and N-donor ligands through a mixed-ligand synthetic strategy.

Syntheses, structures, and luminescence properties of four metal–organic polymers with undocumented topologies constructed from 3,5-bis((4′-carboxylbenzyl)oxy)benzoate ligand

Four 3D metal–organic polymers with new topologies based on 3,5-bis((4′-carboxylbenzyl)oxy)benzoic acid were synthesized and characterized.