Xn:Harmful;
111-27-3Relevant articles and documents
Oxyfunctionalization of Alkanes with H2O2 catalysed by Vanadium Silicates
Rao, P. R. Hari Prasad,Ramaswamy, A. V.
, p. 1245 - 1246 (1992)
Vanadium silicate molecular sieves can catalyse the oxyfunctionalization of alkanes to corresponding alcohols, aldehydes and ketones; they are able to oxidise the primary carbon atom as well.
Highly Efficient Photocatalytic Degradation of Dyes by a Copper–Triazolate Metal–Organic Framework
Liu, Chen-Xia,Zhang, Wen-Hua,Wang, Nan,Guo, Penghu,Muhler, Martin,Wang, Yuemin,Lin, Shiru,Chen, Zhongfang,Yang, Guang
, p. 16804 - 16813 (2018)
A copper(I) 3,5-diphenyltriazolate metal–organic framework (CuTz-1) was synthesized and extensively characterized by using a multi-technique approach. The combined results provided solid evidence that CuTz-1 features an unprecedented Cu5tz6 cluster as the secondary building unit (SBU) with channels approximately 8.3 ? in diameter. This metal–organic framework (MOF) material, which is both thermally and chemically (basic and acidic) stable, exhibited semiconductivity and high photocatalytic activity towards the degradation of dyes in the presence of H2O2. Its catalytic performance was superior to that of reported MOFs and comparable to some composites, which has been attributed to its high efficiency in generating .OH, the most active species for the degradation of dyes. It is suggested that the photogenerated holes are trapped by CuI, which yields CuII, the latter of which behaves as a catalyst for a Fenton-like reaction to produce an excess amount of .OH in addition to that formed through the scavenging of photogenerated electrons by H2O2. Furthermore, it was shown that a dye mixture (methyl orange, methyl blue, methylene blue, and rhodamine B) could be totally decolorized by using CuTz-1 as a photocatalyst in the presence of H2O2 under the irradiation of a Xe lamp or natural sunlight.
Interfacial Sites in Ag Supported Layered Double Oxide for Dehydrogenation Coupling of Ethanol to n-Butanol
Zhang, Jian,Shi, Kai,Zhu, Yanru,An, Zhe,Wang, Wanning,Ma, Xiaodan,Shu, Xin,Song, Hongyan,Xiang, Xu,He, Jing
, p. 1095 - 1103 (2021)
Upgrading of ethanol to n-butanol through dehydrogenation coupling has received increasing attention due to the wide application of n-butanol. But the enhancement of ethanol dehydrogenation and followed coupling to produce high selectivity to n-butanol is still highly desired. Our previous work has reported an acid-base-Ag synergistic catalysis, with Ag particles supported on Mg and Al-containing layered double oxides (Ag/MgAl-LDO). Here, Ag-LDO interfaces have been manipulated for dehydrogenation coupling of ethanol to n-butanol by tailoring the size of Ag particles and the interactions between Ag and LDO. It has been revealed that increasing the population of surface Ag sites at Ag-LDO interfaces promotes not only the dehydrogenation of ethanol to acetaldehyde but also the subsequent aldol condensation of generated acetaldehyde. A selectivity of up to 76 % to n-butanol with an ethanol conversion of 44 % has been achieved on Ag/LDO with abundant interfacial Ag sites, much superior to the state-of-the-art catalysts.
New selectivities from old catalysts. Occlusion of Grubbs' catalysts in PDMS to change their reactions
Brett Runge,Mwangi, Martin T.,Bowden, Ned B.
, p. 5278 - 5288 (2006)
This article describes new selectivities for Grubbs' first and second generation catalysts when occluded in a hydrophobic matrix of polydimethylsiloxane (PDMS). Occlusion of catalysts in mm-sized slabs of PDMS is accomplished by swelling with methylene chloride then removing the solvent under vacuum. The catalysts are homogenously dissolved in PDMS yet remain catalytically active. Many substrates that react by olefin metathesis with Grubbs' catalysts freely dissolved in methylene chloride also react by olefin isomerization with occluded catalysts. Eleven examples of substrates that exhibit dual reactivity by undergoing olefin isomerization with occluded catalysts and olefin metathesis with catalysts dissolved in methylene chloride are reported. Most of these substrates have olefins with allylic phosphine oxides, carbonyls, or ethers. Control experiments demonstrate that isomerization is occurring in the solvent by decomposition of the catalyst from a ruthenium carbene to a proposed ruthenium hydride. This work was extended by heating occluded Grubbs' first generation catalyst to 100 °C in 90% MeOH in H2O in the presence of various alkenes to transform the Grubbs' catalyst into an isomerization catalyst for unfunctionalized olefins. This work demonstrates that occlusion of organometallic catalysts in PDMS has important implications for their reactions and can be used as a method to control which reactions they catalyze.
Thermal desulfurization of (Alkoxymethyl)thiiranes
Nalet'Ko,Pervova,Gorbunova,Zapevalov, A. Ya,Toporova,Saloutin
, p. 2120 - 2124 (2014)
Reaction of (alkoxymethyl)oxiranes with thiourea in methanol has afforded the corresponding thiiranes, and catalyst-free thermal desulfurization of the products has been studied. The major products of desulfurization are alcohols and alkenes, both in the cases of (polyfluoroalkyloxymethyl)thiiranes and their non-fluorinated analogs. Longer alkyl chain in thiiranes favors formation of alcohols over alkenes formation in the course of desulfurization.
Mechanistic study of the selective hydrogenation of carboxylic acid derivatives over supported rhenium catalysts
Toyao, Takashi,Ting, Kah Wei,Siddiki, S. M. A. Hakim,Touchy, Abeda S.,Onodera, Wataru,Maeno, Zen,Ariga-Miwa, Hiroko,Kanda, Yasuharu,Asakura, Kiyotaka,Shimizu, Ken-ichi
, p. 5413 - 5424 (2019)
The structure and performance of TiO2-supported Re (Re/TiO2) catalysts for selective hydrogenation of carboxylic acid derivatives have been investigated. Re/TiO2 promotes selective hydrogenation reactions of carboxylic acids and esters that form the corresponding alcohols, and of amides that generate the corresponding amines. These processes are not accompanied by reduction of aromatic moieties. A Re loading amount of 5 wt% and a catalyst pretreatment with H2 at 500 °C were identified as being optimal to obtain the highest catalytic activity for the hydrogenation processes. The results of studies using various characterization methods, including X-ray diffraction (XRD), X-ray absorption fine structure (XAFS), X-ray photoelectron spectroscopy (XPS), and scanning transmission electron microscopy (STEM), indicate that the Re species responsible for the catalytic hydrogenation processes have sub-nanometer to a few nanometer sizes and average oxidation states higher than 0 and below +4. The presence of either a carboxylic acid and/or its corresponding alcohol is critical for preventing the Re/TiO2 catalyst from promoting production of dearomatized byproducts. Although Re/TiO2 is intrinsically capable of hydrogenating aromatic rings, carboxylic acids, alcohols, amides, and amines strongly adsorb on the Re species, which leads to suppression of this process. Moreover, the developed catalytic system was applied to selective hydrogenation of triglycerides that form the corresponding alcohols.
Epoxidation of Alkenes with O2 Catalyzed by EuCl3 under Ambient Conditions
Yamanaka, Ichiro,Nakagaki, Katsumi,Akimoto, Takashi,Otsuka, Kiyoshi
, p. 1717 - 1720 (1994)
EuCl3 dissolved in a mixture of propanoic acid and 1,2-dichloroethane catalyzed the epoxidation of 1-hexene (81.4percent selectivity, 5.34percent yield for 1h) with O2 in the presence of Zn powder at 40 deg C.The epoxidation was also catalyzed by LaCl3 (0.75percent yield) and SmCl3 (0.57percent yield), but CeCl3 (0.08percent yield) was inactive.Epoxidations of styrene and cyclohexene were also promoted by the EuCl3-catalytic system.
LiBH4-promoted Hydroboration of Alkenes with 1,3,2-Benzodioxaborole
Arase, Akira,Nunokawa, Yutaka,Masuda, Yuzuru,Hoshi, Masayuki
, p. 205 - 206 (1991)
In the presence of a small amount of LiBH4 mono-, di-, tri- and tetr-substituted ethenes were hydroborated almost quantitatively with 1,3,2-benzodioxaborole (catecholborane) under very mild conditions.
Catalytic conversion of ethanol into an advanced biofuel: Unprecedented selectivity for n-butanol
Dowson, George R. M.,Haddow, Mairi F.,Lee, Jason,Wingad, Richard L.,Wass, Duncan F.
, p. 9005 - 9008 (2013)
Taming the beast: Unprecedented selectivity of over 94 % at good (20 %+) conversion was observed for the upgrade of ethanol to the advanced biofuel 1-butanol with a ruthenium diphosphine catalyst (see picture; P orange, Ru blue). Preliminary mechanistic studies indicate that control over the notoriously uncontrolled acetaldehyde aldol condensation is critical for the high selectivity, and evidence was found for an on-metal condensation step. Copyright
Supported nickel-rhenium catalysts for selective hydrogenation of methyl esters to alcohols
Liu, Kaituo,Pritchard, James,Lu, Li,Van Putten, Robbert,Verhoeven,Schmitkamp, Mike,Huang, Xiaoming,Lefort, Laurent,Kiely, Christopher J.,Hensen, Emiel J. M.,Pidko, Evgeny A.
, p. 9761 - 9764 (2017)
The addition of Re to Ni on TiO2 yields efficient catalysts for the hydrogenation of acids and esters to alcohols under mild conditions. Rhenium promotes the formation of atomically dispersed and sub-nanometre-sized bimetallic species interacting strongly with the oxide support.
