[신간의 별자리x] 우리/미술, 그리고 ‘슬픔의 박물관’

Recent Advances in Polyoxometalate-Catalyzed Reactions

Novel catalytic materials are highly demanded to perform a variety of catalytic organic reactions. MOFs combine the benefits of heterogeneous catalysis like easy post reaction separation, catalyst reusability, high stability and homogeneous catalysis such as high efficiency, selectivity, controllability and mild reaction conditions. The possible organization of active centers like metallic nodes, organic linkers, and their chemical synthetic functionalization on the nanoscale shows potential to build up MOFs particularly modified for catalytic challenges. In this review, we have summarized the recent research progress in heterogeneous catalysis by MOFs and their catalytic behavior in various organic reactions, highlighting the key features of MOFs as catalysts based on the active sites in the framework. Examples of their post functionalization, inclusion of active guest species and metal nanoparticles have been discussed. Finally, the use of MOFs as catalysts for asymmetric heterogeneous catalysis and stability of MOFs has been presented as separate sections.

Metal–organic frameworks: versatile heterogeneous catalysts for efficient catalytic organic transformations

Concern over the economics of accessing fossil fuel reserves, and widespread acceptance of the anthropogenic origin of rising CO2 emissions and associated climate change from combusting such carbon sources, is driving academic and commercial research into new routes to sustainable fuels to meet the demands of a rapidly rising global population. Here we discuss catalytic esterification and transesterification solutions to the clean synthesis of biodiesel, the most readily implemented and low cost, alternative source of transportation fuels to meet future societal demands.

/pdf/heterogeneous-catalysis-for-sustainable-biodiesel-production-wruq11o683.pdf

Heterogeneous catalysis for sustainable biodiesel production via esterification and transesterification

Two novel polyoxometalate (POM)-based metal–organic frameworks (MOFs), [TBA]3[e-PMoV8MoVI4O36(OH)4Zn4][BTB]4/3·xGuest (NENU-500, BTB = benzene tribenzoate, TBA+ = tetrabutylammonium ion) and [TBA]3[e-PMoV8MoVI4O37(OH)3Zn4][BPT] (NENU-501, BPT = [1,1′-biphenyl]-3,4′,5-tricarboxylate), were isolated. In these compounds, the POM fragments serving as nodes were directly connected with organic ligands giving rise to three-dimensional (3D) open frameworks. The two anionic frameworks were balanced by TBA+ ions residing inside the open channels. They exhibit not only good stability in air but also tolerance to acidic and basic media. Furthermore, they were employed as electrocatalysts for the hydrogen evolution reaction (HER) owing to the combination of the redox activity of a POM unit and the porosity of a MOF. Meanwhile, the HER activities of e(trim)4/3, NENU-5, and HKUST-1 were also studied for comparison. Remarkably, as a 3D hydrogen-evolving cathode operating in acidic electrolytes, NENU-500 exhibits the hig...

Ultrastable Polymolybdate-Based Metal–Organic Frameworks as Highly Active Electrocatalysts for Hydrogen Generation from Water

Cs Salt of Undecatungstophospho(aqua) Cuprate(II): Microwave Synthesis, Characterization, Catalytic and Kinetic Study for Epoxidation of cis‐Cyclooctene with TBHP

Stabilized Pd(0) nanoparticles by supported 12-tungstophosphoric acid (Pd(0)-TPA/ZrO2) was explored as a sustainable recyclable catalyst for selective C=C hydrogenation of cyclohexene and crotonaldehyde. The catalyst shows an outstanding performance [catalyst to substrate ratio (1:1.31 × 104)] towards high conversion as well as 100% selectivity of the desired product with high turnover number (> 10,000) and turnover frequency (> 2600 h−1) for both the systems. The use of neat water as a solvent and mild reaction conditions makes the present system environmentally benign and green. Moreover, the catalyst could be recovered and reused up to five cycles without any significant loss in their conversion as well as selectivity. The viability of the catalyst was evaluated towards different aromatic as well as aliphatic arenes and found to be excellent in all the cases. The obtained selectivity, especially butyraldehyde, was correlated with the nature of the catalyst as well as solvent and based on the study, a plausible mechanism for both the reactions was also proposed.

Selective C=C Hydrogenation of Unsaturated Hydrocarbons in Neat Water Over Stabilized Palladium Nanoparticles Via Supported 12-Tungstophosphoric Acid

A solid acid catalyst comprising of lacunary silicotungstate and zirconia was synthesized and characterized by physicochemical techniques. Surface morphologies of support and catalyst were studied by scanning electron microscopy. Catalytic properties were evaluated for the esterification of n-butanol with acetic acid. Esterifications of sec-butanol and isobutanol with acetic acid as well as the esterification of n-butanol with different acids such as formic acid and propionic acid were carried out under optimized conditions. Catalytic activities for calcined as well as recycled catalysts were also evaluated for the esterification under optimized condition.

Keggin-type mono lacunary silicotungstate supported onto zirconia: synthesis, characterization, and esterification reaction

Cs salt of di-manganese(II) substituted phosphotungstate: One pot synthesis, structural, spectroscopic characterization and solvent free liquid phase oxidation of styrene using different oxidants

Anjali Patel

Papers

Cs Salt of Undecatungstophospho(aqua) Cuprate(II): Microwave Synthesis, Characterization, Catalytic and Kinetic Study for Epoxidation of cis‐Cyclooctene with TBHP

Selective C=C Hydrogenation of Unsaturated Hydrocarbons in Neat Water Over Stabilized Palladium Nanoparticles Via Supported 12-Tungstophosphoric Acid

Keggin-type mono lacunary silicotungstate supported onto zirconia: synthesis, characterization, and esterification reaction

Cs salt of di-manganese(II) substituted phosphotungstate: One pot synthesis, structural, spectroscopic characterization and solvent free liquid phase oxidation of styrene using different oxidants

Functionalization of Keggin type manganese substituted phosphotungstate by R-(−)-1-cyclohexylethylamine: Synthesis and characterization