86-81-7Relevant articles and documents
Highly dispersed cobalt oxide nanoparticles on manganese oxide nanotubes for aerobic oxidation of benzyl alcohol
Reddy, Velma Ganga,Jampaiah, Deshetti,Chalkidis, Anastasios,Sabri, Ylias M.,Mayes, Edwin L.H.,Bhargava, Suresh K.
, (2019)
Hybrid Co3O4/MnO2 nanotube-based catalysts were prepared by a simple hydrothermal synthesis method. The physico-chemical properties of Co3O4/MnO2 catalyst were then studied by different characterization techniques, namely, SEM, TEM and HR-TEM, XRD, BET surface area, XPS and H2-TPR. The hybrid catalyst showed superior catalytic performance toward benzyl alcohol oxidation than pure MnO2 nanotubes and Co3O4 nanoparticles. The uniform dispersion of Co3O4 nanoparticles, good redox behaviour, the variable oxidation states of manganese and cobalt (Mn3+/4+ or Co3+/2+) as well as the abundance of active surface oxygen species were responsible for such a high catalytic activity.
Reversible Redox Activity in Multicomponent Metal-Organic Frameworks Constructed from Trinuclear Copper Pyrazolate Building Blocks
Tu, Binbin,Pang, Qingqing,Xu, Huoshu,Li, Xiaomin,Wang, Yulin,Ma, Zhen,Weng, Linhong,Li, Qiaowei
, p. 7998 - 8007 (2017)
Inorganic functionalization of metal-organic frameworks (MOFs), such as incorporation of multiple inorganic building blocks with distinct metals into one structure and further modulation of the metal charges, endows the porous materials with significant properties toward their applications in catalysis. In this work, by an exploration of the role of 4-pyrazolecarboxylic acid (H2PyC) in the formation of trinuclear copper pyrazolate as a metalloligand in situ, four new MOFs with multiple components in order were constructed through one-pot synthesis. This metalloligand strategy provides multicomponent MOFs with new topologies (tub for FDM-4 and tap for FDM-5) and is also compatible with a second organic linker for cooperative construction of complex MOFs (1,4-benzenedicarboxylic acid for FDM-6 and 2,6-naphthalenedicarboxylic acid for FDM-7). The component multiplicity of these MOFs originates from PyC's ability to separate Cu and Zn on the basis of their differentiated binding affinities toward pyrazolate and carboxylate. These MOFs feature reversible and facile redox transformations between CuI3(PyC)3 and CuII3(μ-OH)(PyC)3(OH)3 without altering the connecting geometries of the units, thus further contributing to the significant catalytic activities in the oxidation of CO and aromatic alcohols and the decomposition of H2O2. This study on programming multiple inorganic components into one framework and modulating their electronic structures is an example of functionalizing the inorganic units of MOFs with a high degree of control.
Polyaniline supported vanadium catalyzed aerobic oxidation of alcohols to aldehydes and ketones
Reddy, Sabbasani Rajasekhara,Das, Subhabrata,Punniyamurthy
, p. 3561 - 3564 (2004)
Polyaniline supported vanadium complex 1 catalyzes efficiently the oxidation of alcohols to aldehydes and ketones in high yields under molecular oxygen in toluene at ca. 100°C. The catalyst 1 can be recycled without loss of activity.
Visible-Light-Induced Selective C-C Bond Cleavage Reactions of Dimeric β-O-4 and β-1 Lignin Model Substrates Utilizing Amine-Functionalized Fullerene
Cho, Dae Won,Jang, Hannara,Kim, Min-Ji,Kim, Young-Il,Lim, Dong Hyun,Lim, Suk Hyun,Wee, Kyung-Ryang
, p. 2289 - 2300 (2022/02/07)
Finding a selective and efficient fragmentation process under ambient conditions is pivotal for the generation of fuels and chemical feedstocks from lignoceullosic biomass. In the present study, visible-light and amine-functionalized fullerene-based photocatalyst-promoted photodegradation reactions of dimeric β-O-4 and β-1 lignin model compounds, containing varying numbers of methoxy substituents on the arene ring, were explored to find and develop mild, eco-friendly photochemical techniques for efficient delignification. The results showed that, in contrast to well-known organic photoredox catalysts, amine-functionalized fullerene photocatalyst promoted photochemical reactions of lignin model compounds could lead to more efficient lignin fragmentation reactions through a pathway involving a selective Cα-Cβ bond cleavage process, and in addition, Cα-hydroxyl moiety in lignin model compounds played a significant role in the success of the Cα-Cβ bond cleavage reaction of lignin model substrates.
Synthesis, characterization, reactivity, and catalytic studies of heterobimetallic vanadium(V) complexes containing hydrazone ligands
Borthakur, Rosmita,Dhanpat, Shobha A.,Kumar, Arvind,Kurbah, Sunshine D.,Lal, Ram A.,Syiemlieh, Ibanphylla
, (2020/10/21)
Six heterobimetallic alkali metal dioxidovanadium(V) coordination polymer complexes {[M6{VO(μ-O)}2(μ-OH)4(μ4-slox/nph)].n DMF}∞ where M = Na, K, and Cs; n = 1 for (1), 0 for (2)-(6) of two dihydrazone ligands, disalicylaldehydeoxaloyldihydrazone (H4slox) and bis(2-hydroxy-1-naphthaldehyde)oxaloyldihydrazone (H4nph) are reported. All the complexes have been characterized by various physicochemical techniques such as elemental analyses, molar conductance, IR, NMR, UV–vis, and cyclic voltammetry. The IR, 1HNMR, and 13CNMR spectral data suggest that the dihydrazones are coordinated through phenolate/naphtholate oxygen, enolate oxygen, and azine nitrogen atoms to the metal centres. The structure of complex {[Na6{VO(μ-O)}2(μ-OH)4(μ4-slox)].DMF}∞ (1) is also determined by single-crystal X-ray data, which revealed that the H4slox coordinated via all possible dative sites to metal centres as tetrabasic octadentate ligand. The vanadium metal centres adopted distorted square-pyramidal coordination geometries, and the sodium atoms are also in five coordination atmospheres. The electronic spectra of the complexes showed LMCT bands in addition to intra-ligand π → π* and n → π* transitions. As evident from the cyclic voltammetry, the complexes showed two metal-centred electron transfer reactions {[(VVVV(slox)2?/VVVIV(slox)3?] and [(VVVIV(slox)3?/VVVIV(slox)4?]}, in addition to the ligand centred electron transfer reactions. Further, bovine serum albumin (BSA interaction studies of the complexes {[Na6{VO(μ-O)}2(μ-OH)4(μ4-slox)].DMF}∞ (1) and [Na6{VO(μ-O)}2(μ-OH)4(μ4-nph)]∞ (4) revealed strong binding affinity. Moreover, the catalytic studies of the complexes (1) and (4) were found to be effective for the oxidation of alcohols into their corresponding aldehydes and ketones and bromination of some organic substrates in the presence of H2O2 as an oxidizing agent.