1D Zn(II) Coordination Polymers as Effective Heterogeneous Catalysts in Microwave-Assisted Single-Pot Deacetalization-Knoevenagel Tandem Reactions in Solvent-Free Conditions

Tandem Deacetalization-Knoevenagel Condensation Reactions for the Synthesis of Benzylidene Malononitrile Using Ruthenium(II) Cymene Complexes

In this study, we report the synthesis and full characterization of five novel ruthenium(II) cymene complexes with the general formula [Ru(cym)(L')Cl], featuring N,O- and N,N-coordinating pyrazolone-based hydrazone ligands. We have characterized these complexes using single X-ray crystallography, Fourier-transform infrared spectroscopy (FT-IR), Nuclear magnetic resonance (NMR), elemental analysis, and Electrospray Ionization Mass Spectroscopy (ESI-MS). Crystallographic analysis confirmed that all of the complexes have a similar type of half-sandwich, pseudo-octahedral "three-legged piano-stool" geometry where the cymene moiety displays the typical η6-coordination mode and the hydrazone ligands coordinate to the Ru(II) center in a bidentate fashion. These complexes, with multiple catalytic sites, demonstrated high efficiency in catalyzing one-pot cascade deacetalization-Knoevenagel condensation reactions under mild conditions, achieving up to 92% of final product yield at 75 °C after 4 h of reaction time under solvent-free condition. Additionally, DFT calculations provided insight into the catalytic mechanism, suggesting a pathway driven by metal-ligand cooperation, assisted by the basic oxygen site of the pyrazolone ring and by the weakly acidic character of the NNH proton of the hydrazone group.

Bifunctional Metal-Organic Nanoballs Featuring Lewis Acidic and Basic Sites as a New Platform for One-Pot Tandem Catalysis

The design and synthesis of polyhedra using coordination-driven self-assembly has been an intriguing research area for synthetic chemists. Metal-organic polyhedra are a class of intricate molecular architectures that have garnered significant attention in the literature due to their diverse structures and potential applications. Hereby, we report Cu-MOP, a bifunctional metal-organic cuboctahedra built using 2,6-dimethylpyridine-3,5-dicarboxylic acid and copper acetate at room temperature. The presence of both Lewis basic pyridine groups and Lewis acidic copper sites imparts catalytic activity to Cu-MOP for the tandem one-pot deacetalization-Knoevenagel/Henry reactions. The effect of solvent system and time duration on the yields of the reactions was studied, and the results illustrate the promising potential of these metal-organic cuboctahedra, also known as nanoballs for applications in catalysis.

Designing and Construction of Polyaromatic Group Containing Cd(II)-based Coordination Polymers for Solvent-free Strecker-type Cyanation of Acetals

In the present work, we have synthesized and characterized two novel Cd(II) coordination polymers, [Cd4(L1)4(DMF)6]n.3n(DMF) (1) and [Cd2(L2)2(DMF)3]n.2n(DMF) (2), and studied their catalytic application. They were synthesized via solvothermal reaction...

Crystal structure of poly[bis(μ2-2,6-bis(1-imidazoly)pyridine-κ2 N,N′)-bis(thiocyanato-κ1 N)copper(II)] dithiocyanate, C24H18CuN12S2

C24H18CuN12S2, monoclinic, P21/c (no. 4), a = 11.038(2) Å, b = 8.9312(18) Å, c = 16.083(5) Å, β = 125.66(2)°, V = 1288.2(6) Å3, Z = 2, R gt (F) = 0.0265, wR ref (F 2) = 0.0974, T = 293 K.

Crystal structure of [aqua-(4-iodopyridine-2,6-dicarboxylato-κ3 O,N,O′)-(1,10-phenanothroline-κ2 N,N′)copper(II)] dihydrate, C19H16O7N3CuI

C19H16O7N3CuI, orthorhombic, Pbca (no. 61), a = 12.5772(2) Å, b = 17.3473(3) Å, c = 18.8445(3) Å, Z = 8, V = 4111.50(12) Å3, R gt (F) = 0.0310, wR ref (F 2) = 0.0775, T = 289 K.