2825-82-3Relevant articles and documents
Preparation method of adamantanone
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Paragraph 0033; 0043; 0052; 0062; 0070; 0080; 0088; 0098;, (2021/04/03)
The invention discloses a preparation method of adamantanone, and relates to the technical field of adamantanone synthesis. The problems that the reaction time is long and the operation process is tedious are solved. The preparation method specifically comprises the following steps: putting raw materials including adamantane, sulfuric acid and trifluoroacetic acid into a batching kettle, and stirring and mixing at 30 DEG C; raising the temperature to 50 DEG C, and introducing nitrogen into the batching kettle; pressing the mixed materials into a reaction tube, and performing standing for 1 minute; pouring the reaction solution on 500g of ice, adding a NaOH aqueous solution which is 7 times the weight of adamantane during cooling, and adjusting the pH value to 9; and extracting by using methylbenzene of which the weight is 3 times that of adamantane. The raw materials are mixed and then heated, nitrogen is introduced, then an oxidation reaction occurs, the retention time and temperatureof reaction liquid in a reaction tube are controlled in the leading-out period, the reaction liquid is extracted through methylbenzene and the NaOH aqueous solution, the extraction liquid is subjected to reduced pressure distillation concentration, cooling, separation and drying treatment, the final product is obtained, the operation process is relatively simple, the reaction is controllable, andthe time is short.
Dendrimer-Encapsulated Pd Nanoparticles, Immobilized in Silica Pores, as Catalysts for Selective Hydrogenation of Unsaturated Compounds
Karakanov, Edward A.,Zolotukhina, Anna V.,Ivanov, Andrey O.,Maximov, Anton L.
, p. 358 - 381 (2019/04/04)
Heterogeneous Pd-containing nanocatalysts, based on poly (propylene imine) dendrimers immobilized in silica pores and networks, obtained by co-hydrolysis in situ, have been synthesized and examined in the hydrogenation of various unsaturated compounds. The catalyst activity and selectivity were found to strongly depend on the carrier structure as well as on the substrate electron and geometric features. Thus, mesoporous catalyst, synthesized in presence of both polymeric template and tetraethoxysilane, revealed the maximum activity in the hydrogenation of various styrenes, including bulky and rigid stilbene and its isomers, reaching TOF values of about 230000 h?1. Other mesoporous catalyst, synthesized in the presence of polymeric template, but without addition of Si(OEt)4, provided the trans-cyclooctene formation with the selectivity of 90–95 %, appearing as similar to homogeneous dendrimer-based catalysts. Microporous catalyst, obtained only on the presence of Si(OEt)4, while dendrimer molecules acting as both anchored ligands and template, demonstrated the maximum activity in the hydrogenation of terminal linear alkynes and conjugated dienes, reaching TOF values up to 400000 h?1. Herein the total selectivity on alkene in the case of terminal alkynes and conjugated dienes reached 95–99 % even at hydrogen pressure of 30 atm. The catalysts synthesized can be easily isolated from reaction products and recycled without significant loss of activity.
Colloidal and nanosized catalysts in organic synthesis: XV. Gas-phase hydrogenation of alkenes catalyzed by supported nickel nanoparticles
Popov, Yu. V.,Mokhov,Nebykov,Latyshova,Panov,Dontsova,Shirkhanyan,Shcherbakova
, p. 2589 - 2593 (2017/03/22)
Gas-phase hydrogenation of alkenes and their derivatives, catalyzed by nickel nanoparticles supported on zeolite or silica gel support occurs at 150–250°С and an atmospheric hydrogen pressure and results in a high conversion. The selectivity of the hydrogenation depends on the amount of hydrogen: at a low diene (triene)–hydrogen ratio, selective hydrogenation of one multiple bond in the substrate is possible.
Hydrogenation of alkenes over nickel nanoparticles under atmospheric pressure of hydrogen
Mokhov,Popov, Yu. V.,Nebykov
, p. 319 - 323 (2016/06/06)
Nickel nanoparticles have been shown to be an accessible catalyst which allows hydrogenation of unsaturated compounds to be accomplished under atmospheric pressure of hydrogen at relatively low temperatures. Linear and cyclic alkenes, styrene and norbornene derivatives, as well as pinenes and camphene have been smoothly hydrogenated under these conditions. In some cases, selective hydrogenation of unsaturated carbon–carbon bond is possible with the other functional group remaining intact.
Oxygen-Deficient Tungsten Oxide as Versatile and Efficient Hydrogenation Catalyst
Song, Jiajia,Huang, Zhen-Feng,Pan, Lun,Zou, Ji-Jun,Zhang, Xiangwen,Wang, Li
, p. 6594 - 6599 (2015/11/18)
Heterogeneous hydrogenation is one of the most important industrial operations, and reduced metals (mostly noble metals and a few inexpensive metals) generally serve as the catalyst to activate molecular H2. Herein we report oxygen-deficient tungsten oxide, such as WO2.72, is a versatile and efficient catalyst for the hydrogenation of linear olefins, cyclic olefins, and aryl nitro groups, with obvious advantages compared with non-noble metal nickel catalyst from the aspect of activity and selectivity. Density functional theory calculations prove the oxygen-deficient surface activates H2 very easily in both kinetics and thermodynamics. Testing on several oxygen-deficient tungsten oxides shows a linear dependence between the hydrogenation activity and oxygen vacancy concentration. Tungsten is earth-abundant, and WO2.72 can be synthesized in large scale using a low-cost procedure, which provides an ideal catalyst for industrial application. Because oxygen vacancy is a common characteristic of many metal oxides, the findings in this work may be extended to other metal oxides and thus provide the possibility for exploring a new type of hydrogenation catalyst.
Catalyst-free hydrogenation of alkenes and alkynes with hydrazine in the presence of oxygen
Menges, Nurettin,Balci, Metin
, p. 671 - 676 (2014/04/03)
A series of alkenes and alkynes was subjected to reduction with hydrazine hydrate in ethanol in the presence of oxygen. An efficient method was developed for the reduction of C-C double bonds and C-C triple bonds with diimide, generated in situ from hydrazine hydrate by oxidation with oxygen. The reduction process proceeded for 24-48? hours with high chemoselectivity and excellent yields. This reduction procedure offers synthetic advantages over metal-catalyzed hydrogenation as well as other systems. Georg Thieme Verlag Stuttgart New York.
Highly selective mono-hydrogenation of dicyclopentadiene with Pd-nanoparticles
Behr, Arno,Manz, Vanessa,Lux, Adrian,Ernst, Andrea
, p. 241 - 245 (2013/07/27)
In this paper, we present a new protocol to synthesize dihydrodicyclopentadienes (DHDCP), via mono hydrogenation of dicyclopentadiene. With the use of Pd-nanoparticles as catalysts the products are formed highly selective under mild conditions. The ratio between the DHDCP and the tetrahydrodicyclopentadiene (THDCP) can be shifted by variation of the hydrogen pressure from 7:1 to 1:8, with high conversions of over 85 %. The product DHDCP is an essential building block in co-polymerizations. Also we show an easy recycling concept for the nanocatalyst by phase separation. With simple filtration the solid products DHDCP and THDCP can be isolated and the liquid catalyst phase can directly be reused. Over all recycling runs a steady high conversion of about 75 % was observed.
Selective hydrogenation of alkenes under ultramild conditions
Pandarus, Valerica,Gingras, Genevieve,Beland, Francois,Ciriminna, Rosaria,Pagliaro, Mario
experimental part, p. 1230 - 1234 (2012/07/28)
SiliaCat Pd0 solid catalyst heterogeneously mediates at room temperature the selective hydrogenation of a wide variety of alkenes under hydrogen balloon conditions using a modest 0.1 mol % catalyst amount. The catalyst is recyclable with negligible leaching of valued palladium, providing the chemical industry with a suitable replacement for less selective metal-based catalysts.
Cycloisomerization and [2 + 2]cyclodimerization of 1,5-cyclooctadiene catalyzed with the Ni(COD)2/BF3·OEt2 system
Saraev,Kraikivskii,Matveev,Bocharova,Petrovskii,Zelinskii,Vilms,Klein, Hans-Friedrich
scheme or table, p. 231 - 238 (2010/05/12)
The catalytic system Ni(COD)2/BF3·OEt2 has been studied in conversions of 1,5-cyclooctadiene under argon and ethylene atmosphere. It has been demonstrated that the catalytic system formed under argon exhibits a high effectiveness in cycloisomerization of 1,5-COD surpassing in this characteristic all known nickel complex catalysts (selectivity to bicyclo-[3.3.0]-octene-2 is up to 99.5% at 100% conversion). In the case of ethylene atmosphere the system produces mainly dimers (yield of cyclodimers above 70%). It has been shown that the catalytic system Ni(COD)2/BF3·OEt2 has the feature of "a living catalyst" consisting in resuming the initial activity with a new portion of 1,5-COD added when the monomer was fully exhausted. The main and side products of the 1,5-COD conversion have been identified with GC-MS and preparative liquid chromatography combined with NMR and IR spectroscopy. Based on EPR and IR spectroscopic data a mechanism for the catalytic performance of the Ni(COD)2/BF3·OEt2 system in argon or ethylene atmospheres is suggested. It has been shown that Ni(0) is oxidized by the Lewis acid to Ni(I) which is stabilized by substrate molecules in a mononuclear form without involvement of conventional organoelement entities. Three sorts of paramagnetic nickel species have been found: ionic complexes containing π-coordinated COD ligands; ionic complexes σ-bonded to COD; complexes as intimate pairs with BF4- counter ions. A mechanism for the catalytic conversion of 1,5-cyclooctadiene is proposed.
PROCESS FOR PRODUCING ADAMANTANE
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Page/Page column 7, (2008/06/13)
The present invention provides a process of an industrially advantageous production of high-purity adamantane at a low cost and with a high efficiency by isomerizing trimethylenenorbornane contained in a raffinate obtained from a platfinate.
