Two Series of Tetranuclear Ln(III)-Based Clusters: Structures, Magnetic Behaviors, and Efficient Cycloaddition of CO₂ to Oxazolidinones

Abstract

Four new and interesting Ln4 clusters formulated as [Ln4(NO3)2(acac)4(HL1)2(CH3OH)2]·2(CH3CN)] (Ln = Gd(1), Dy(2); H4L1 = 2-(hydroxymethyl)-2-(((2-hydroxynaphthalen-1-yl)methylene)amino)propane-1,3-diol); acac = acetylacetone) and [Ln4(NO3)2(acac)4(L2)2(CH3CH2OH)2] (Ln = Gd(3), Dy(4); H3L2 = 2-(((2-hydroxynaphthalen-1-yl)methylene)amino)-2-methylpropane-1,3-diol; acac = acetylacetone) were designed and constructed. Single-crystal X-ray studies indicate that all clusters have a defect dicubane topology in which four Ln(III) are on a plane bond with an arrangement of a parallelogram with the μ3-O bridge. The difference between the two series of clusters lies in the change of the ligand substituent and terminal coordinated solvent molecules. All Ln(III)-based clusters 1–4 have exhibited excellent solvent stability. The magnetic investigation suggests that clusters 1 and 3 possess a different magnetothermal effect (−ΔS m = 35.24 J kg–1 K–1 for 1, and −ΔS m = 36.68 J kg–1 K–1 for 3). In addition, the diversity in the environment of the metal center leads to the distinct dynamic behavior of U eff/k B (21.27 K for 2 and 1.96 K for 4) and τ0 (1.43 × 10–7 s for 2 and 2.43 × 10–6 s for 4). More importantly, clusters 1–4 as heterogeneous catalysts can efficiently catalyze the reaction of CO2 with bromopropylene oxide and aromatic amine to synthesize oxazolidinones under mild conditions. By comparison, clusters 1 and 2 show higher catalytic activity than 3 and 4, in which the Brønsted acidic −OH groups working together with Lewis acid metal sites improve the catalytic activity of Ln(III)-based clusters 1 and 2. To the best of our knowledge, it is the first example of Ln(III)-based clusters that show good magnetic property and high catalytic activity simultaneously by regulating the coordination environment of Ln(III) ions. Our work provided a promising direction for regulating properties of multifunctional polynuclear Ln(III)-based clusters via changing the coordinated environment of the metal center. It also helps inspire the development of polynuclear Ln(III)-based multifunctional materials.

Robust {Pb10}-Cluster-Based Metal–Organic Framework for Capturing and Converting CO2 into Cyclic Carbonates under Mild Conditions

“…This process will consume an additional 10–30% of the power plant’s output electricity . Therefore, scientists have begun to develop CO 2 capture and conversion (CCC) technology, which can immediately convert captured CO 2 into socially valuable chemicals and energy through chemical reactions, achieving the goal of killing two birds with one stone. , Although CO 2 is not active enough, the discovery of some efficient catalytic systems has led to industrial applications of some reactions, based on which a number of chemical raw materials are mass-produced, for instance, methanol, salicylic acid, formic acid, and cyclic carbonate. − Among the numerous reactions involved in the conversion of CO 2 , the synthesis of cyclic carbonates using CO 2 as the C1 source is one of the important pathways for the resource utilization of CO 2 . In cycloaddition reactions, some homogeneous catalysts, such as metal-organic complexes, ionic liquids, etc., are widely used. , However, their drawbacks are complex synthesis routes, high costs, difficult product separation, and time- and energy-consuming.…”

Nanoporous Lanthanide-Based MOFs for Catalyzing the Cycloaddition of CO2 and the Knoevenagel Condensation

“…In addition, the extensive use of fossil fuels by humans has led to a significant increase in the emissions of greenhouse gases, such as carbon dioxide (CO 2 ), which form a phenomenon similar to the greenhouse effect in the atmosphere, leading to an increase in Earth’s surface temperature. Therefore, developing new and efficient carbon dioxide capture or utilization technologies is of great significance for reducing carbon dioxide emissions from fossil energy utilization processes and mitigating global warming. − At present, integrated CO 2 capture and utilization technology (ICCU) has received widespread attention due to its advantages of low energy consumption and high efficiency. This technology utilizes a dual functional material to achieve the efficient conversion of CO 2 and obtain carbon-containing fuels by integrating two main processes: CO 2 adsorption and in situ conversion.…”