Substituent effect on iron phthalocyanines as cyclohexene oxidation catalysts

Two iron phthalocyanines peripherally octasubstituted either with electron-withdrawing isobutylsulfonyl moities or electron-donating isobutoxy moieties were designed to investigate the effect of the substitution pattern on their oxidation catalytic activity, and were then tested in oxidation of cyclohexene as a reaction model. For both catalysts, the main product of oxidation was 2-cyclohexen-1-ol which is an allylic oxidation product. The electron-withdrawing isobutylsulfonyl substituted iron phthalocyanine 1exhibited better catalytic activities than the electron-donating isobutoxy substituted iron phthalocyanine 2.

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Development of palladium catalysts modified by ruthenium and molybdenum as anode in direct ethanol fuel cell

Materials for Renewable and Sustainable Energy ◽

10.1007/s40243-020-00187-1 ◽

2021 ◽

Vol 10 (1) ◽

Author(s):

Yonis Fornazier Filho ◽

Ana Caroliny Carvalho da Cruz ◽

Rolando Pedicini ◽

José Ricardo Cezar Salgado ◽

Priscilla Paiva Luz ◽

...

Keyword(s):

Catalytic Activity ◽

Palladium Catalysts ◽

Carbon Support ◽

X Ray Diffraction ◽

Direct Ethanol Fuel Cell ◽

Pd Catalysts ◽

Bifunctional Mechanism ◽

Catalytic Activities ◽

Intrinsic Mechanism ◽

Ternary Catalysts

AbstractPhysical and electrochemical properties of Pd catalysts combined with Ru and Mo on carbon support were investigated. To this end, Pd, Pd1.3Ru1.0, Pd3.2Ru1.3Mo1.0 and Pd1.5Ru0.8Mo1.0 were synthesized on Carbon Vulcan XC72 support by the method of thermal decomposition of polymeric precursors and then physically and electrochemically characterized. The highest reaction yields are obtained for Pd3.2Ru1.3Mo1.0/C and Pd1.5Ru0.8Mo1.0/C and, as demonstrated by thermal analysis, they also show the smallest metal/carbon ratio compared the other catalysts. XRD (X-ray Diffraction) and Raman analyses show the presence of PdO and RuO2 for the Pd/C and the Pd1.3Ru1.0/C catalysts, respectively, a fact not observed for the Pd3.2Ru1.3 Mo1.0 /C and the Pd1.5Ru0.8Mo1.0/C catalysts. The catalytic activities were tested for the ethanol oxidation in alkaline medium. Cyclic voltammetry (CV) shows Pd1.3Ru1.0/C exhibiting the highest peak of current density, followed by Pd3.2Ru1.3Mo1.0/C, Pd1.5Ru0.8Mo1.0/C and Pd/C. From, chronoamperometry (CA), it is possible to observe the lowest rate of poisoning for the Pd1.3Ru1.0/C, followed by Pd3.2Ru1.3Mo1.0/C, Pd1.5Ru0.8Mo1.0/C and Pd/C. These results suggested that catalytic activity of the binary and the ternary catalysts are improved in comparison with Pd/C. The presence of RuO2 activated the bifunctional mechanism and improved the catalytic activity in the Pd1.3Ru1.0/C catalyst. The addition of Mo in the catalysts enhanced the catalytic activity by the intrinsic mechanism, suggesting a synergistic effect between metals. In summary, we suggest that it is possible to synthesize ternary PdRuMo catalysts supported on Carbon Vulcan XC72, resulting in materials with lower poisoning rates and lower costs than Pd/C. Graphic abstract

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Active Pd(ii) complexes: enhancing catalytic activity by ligand effect for carbonylation of methyl nitrite to dimethyl carbonate

Catalysis Science & Technology ◽

10.1039/c7cy01305a ◽

2017 ◽

Vol 7 (17) ◽

pp. 3785-3790 ◽

Cited By ~ 10

Author(s):

Hong-Zi Tan ◽

Zhi-Qiao Wang ◽

Zhong-Ning Xu ◽

Jing Sun ◽

Zhe-Ning Chen ◽

...

Keyword(s):

Catalytic Activity ◽

Dimethyl Carbonate ◽

Ligand Effect ◽

Methyl Nitrite ◽

Catalytic Activities

The catalytic activities of Pd(ii) complexes for carbonylation of methyl nitrite to dimethyl carbonate could be enhanced by ligand effect.

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A graphdiyne-based carbon material for electroless deposition and stabilization of sub-nanometric Pd catalysts with extremely high catalytic activity

Journal of Materials Chemistry A ◽

10.1039/c9ta03621k ◽

2019 ◽

Vol 7 (21) ◽

pp. 13142-13148 ◽

Cited By ~ 12

Author(s):

Liang-Liang Yang ◽

Hong-Juan Wang ◽

Juan Wang ◽

Yu Li ◽

Wen Zhang ◽

...

Keyword(s):

Catalytic Activity ◽

Carbon Material ◽

Electroless Deposition ◽

Suzuki Coupling ◽

High Catalytic Activity ◽

Coupling Reactions ◽

Pd Catalysts ◽

Catalytic Activities

A new graphdiyne-based carbon material was synthesized as an ideal substrate for electroless deposition and stabilization of sub-nanometric Pd catalysts, which showed extremely high catalytic activities for the reduction of nitroarenes and Suzuki coupling reactions.

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Synthesis of concave gold nanocuboids with high-index facets and their enhanced catalytic activity

Chemical Communications ◽

10.1039/c5cc02106e ◽

2015 ◽

Vol 51 (58) ◽

pp. 11591-11594 ◽

Cited By ~ 18

Author(s):

Lidong Li ◽

Yi Peng ◽

Yonghai Yue ◽

Ye Hu ◽

Xiu Liang ◽

...

Keyword(s):

Catalytic Activity ◽

High Index ◽

Catalytic Activities ◽

Growth Method ◽

Seed Mediated

Novel concave gold nanocuboids bounded by 24 high-index {611} facets are synthesized using the seed-mediated growth method via an overgrowth mechanism, which exhibit excellent catalytic activities over certain reactions.

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In Vitro Hepatic Assessment of Cineole and Its Derivatives in Common Brushtail Possums (Trichosurus vulpecula) and Rodents

Biology ◽

10.3390/biology10121326 ◽

2021 ◽

Vol 10 (12) ◽

pp. 1326

Author(s):

Ravneel R. Chand ◽

Mhairi Nimick ◽

Belinda Cridge ◽

Rhonda J. Rosengren

Keyword(s):

Catalytic Activity ◽

Management Strategies ◽

Brushtail Possum ◽

Trichosurus Vulpecula ◽

Cytochrome P450 3A ◽

Phascolarctos Cinereus ◽

Catalytic Activities ◽

Rats And Mice ◽

Drug Metabolising Enzymes

Folivore marsupials, such as brushtail possum (Trichosurus Vulpecula) and koala (Phascolarctos cinereus), can metabolise higher levels of dietary terpenes, such as cineole, that are toxic to eutherian mammals. While the highly efficient drug metabolising enzymes, cytochrome P450 3A (CYP3A) and phase II conjugating enzymes (UDP-glucuronosyltransferase, UGT), are involved in the metabolism of high levels of dietary terpenes, evidence for inhibitory actions on these enzymes by these terpenes is scant. Thus, this study investigated the effect of cineole and its derivatives on catalytic activities of hepatic CYP3A and UGT in mice, rats, and possums. Results showed that cineole (up to 50 µM) and its derivatives (up to 25 µM) did not significantly inhibit CYP3A and UGT activities in mice, rats, and possums (both in silico and in vitro). Interestingly, basal hepatic CYP3A catalytic activity in the possums was ~20% lower than that in rats and mice. In contrast, possums had ~2-fold higher UGT catalytic activity when compared to mice and rats. Thus, these basal enzymatic differences may be further exploited in future pest management strategies.

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Bi-metallic MOF-919 (Fe-Cu) nanozyme capable of bifunctional enzyme-mimicking catalytic activity

Chemical Communications ◽

10.1039/d1cc05908d ◽

2021 ◽

Author(s):

Sivasankar Kulandaivel ◽

Chia-Her Lin ◽

Yi-Chun Yeh

Keyword(s):

Catalytic Activity ◽

Metal Organic Framework ◽

Bifunctional Enzyme ◽

Catalytic Activities ◽

Enzyme Mimicking ◽

Metal Organic ◽

Organic Framework

In this study, we report on a bi-metal organic framework MOF-919 (Fe-Cu) capable of bifunctional-enzyme mimicking activity with oxidase- and peroxidase-like activities. The catalytic activities were examined by using o-phenylenediamine...

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A pyrolysis-free path toward superiorly catalytic nitrogen-coordinated single atom

Science Advances ◽

10.1126/sciadv.aaw2322 ◽

2019 ◽

Vol 5 (8) ◽

pp. eaaw2322 ◽

Cited By ~ 56

Author(s):

Peng Peng ◽

Lei Shi ◽

Feng Huo ◽

Chunxia Mi ◽

Xiaohong Wu ◽

...

Keyword(s):

Catalytic Activity ◽

High Temperature ◽

Oxygen Reduction ◽

Structural Changes ◽

Carbon Matrix ◽

Single Atom ◽

Synthetic Approach ◽

Iron Phthalocyanine ◽

Practical Applications ◽

Single Atoms

Nitrogen-coordinated single-atom catalysts (SACs) have emerged as a frontier for electrocatalysis (such as oxygen reduction) with maximized atom utilization and highly catalytic activity. The precise design and operable synthesis of SACs are vital for practical applications but remain challenging because the commonly used high-temperature treatments always result in unpredictable structural changes and randomly created single atoms. Here, we develop a pyrolysis-free synthetic approach to prepare SACs with a high electrocatalytic activity using a fully π-conjugated iron phthalocyanine (FePc)–rich covalent organic framework (COF). Instead of randomly creating Fe-nitrogen moieties on a carbon matrix (Fe-N-C) through pyrolysis, we rivet the atomically well-designed Fe-N-C centers via intermolecular interactions between the COF network and the graphene matrix. The as-synthesized catalysts demonstrate exceptional kinetic current density in oxygen reduction catalysis (four times higher than the benchmark Pt/C) and superior power density and cycling stability in Zn-air batteries compared with Pt/C as air electrodes.

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