1489-69-6Relevant articles and documents
Microstructured Au/Ni-fiber catalyst: Galvanic reaction preparation and catalytic performance for low-temperature gas-phase alcohol oxidation
Zhao, Guofeng,Deng, Miaomiao,Jiang, Yifeng,Hu, Huanyun,Huang, Jun,Lu, Yong
, p. 46 - 53 (2013)
The highly active and selective gold catalysts were successfully prepared by galvanically depositing Au onto a thin-sheet microfibrous structure consisting of 5 vol.% 8-μm Ni-fiber and 95 vol.% voidage, with high heat conductivity and good stability for the gas-phase oxidation of alcohols. The best catalyst was Au-4/Ni-fiber-300 (Au-loading: 4 wt%; calcined at 300 °C in air), being effective for oxidizing acyclic, benzylic, and polynary (1,2-propanediol) alcohols. For benzyl alcohol, the conversion of 95% was achieved with 99% selectivity to benzaldehyde within 660 h test at 250 °C, while a low ΔT of 2 formed at Au galvanic deposition step into NiO was identified along with the low-temperature activity promotion. This suggests a special synergistic effect between NiO and Au particles, of which comprehensive understanding is particularly desirable.
Erickson,Gordon
, p. 1431 (1973)
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Wiberg,Lavanish
, p. 5272 (1966)
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Scope, Limitation, and Mechanism of the Homoconjugate Electrophilic Addition of Hydrogen Halides
Lambert, Joseph B.,Napoli, James J.,Johnson, Katharine Kappauf,Taba, Kalulu N.,Packard, Beverly Sue
, p. 1291 - 1295 (1985)
Hydrogen halides (HCl, HBr, HI) add by a homoconjugate 1,5 mechanism to cyclopropanes carrying certain electron-withdrawing substituents.When the substituent is COCH3, COC6H5, CO2H, or CN, the reaction gives the 1,3-disubstituted propane in high yield.Addition of DCl gives a product with deuterium only in the position α to the substituent.The order of rates is not in agreement with a mechanism whereby the cyclopropane ring is protonated initially, since the rate of such a process should be slowed by electron-withdrawing groups.The ketones, however, react much more rapidly than benzylcyclopropane, a model for the direct protonation mechanism.The homoconjugate mechanism involves rapid protonation of the side chain, followed by nucleophilic attack on the cyclopropane ring.The reaction is limited to substrates that can be protonated on the side chain to produce an intermediate with charge ajacent to the cyclopropane ring.This charge must be able to be transmitted by resonance to the unsubstituted ring positions in order to facilitate the nucleophilic step.
Cu3Pt1-Cu2O nanocomposites: Synergistic effect-dependent high activity and stability for the gas-phase selective oxidation of alcohols
Liu, Kun,Long, Houkun,Wang, Guangyi,Sun, Yongbin,Hou, Chao,Dong, Jian,Cao, Xiaoqun
, p. 54861 - 54865 (2017)
The catalyst Cu3Pt1-Cu2O/SiC was facilely prepared via the in situ reaction of the corresponding compounds supported on SiC in the reaction stream. Cu3Pt1-Cu2O/SiC exhibits excellent catalytic activity for the oxidation of alcohols (conversion of benzyl alcohol and selectivity of benzyl aldehyde are 93% and 98% respectively). The reduction of active Cu2O to inactive Cu0 is the cause behind the deactivation of Cu/SiC. For Cu3Pt1-Cu2O-7/SiC, a Cu2O-Cu3Pt1 alloy formed under the reaction conditions plays an important role in the reaction. Active 5 nm Cu2O nanoparticles are stabilized by the inactive Cu3Pt1 alloy, which was confirmed by control experiments, characterization results and a three-step experiment.
ELECTROCHEMICAL AND CHEMICAL OXIDATION OF ALCOHOLS IN A TWO-PHASE SYSTEM USING N-OXOPIPERIDINUM SALT: SYNTHESIS OF 4-CHLOROBUTANAL, FORMYLCYCLOPROPANES, AND m-PHENOXYBENZALDEHYDE
Ogibin, Yu. N.,Khusid, A. Kh.,Nikishin, G. I.
, p. 735 - 739 (1992)
Oxidation of 4-chlorobutanol-1, cyclopropylcarbinols, and m-phenoxybenzyl alcohol with electrogenerated bromine, molecular bromine, and sodium hypochlorite using N-oxopiperidinium salt in the two-phase system CH2Cl2-water gave the corresponding carbonyl compounds with good yields.Keywords: indirect electrooxidation, 4-chlorobutanol-1, cyclopropylcarbinols, m-phenoxybenzyl alcohol, 2,2,6,6-tetramethyl-4-benzoyloxypiperidine-1-oxide, bromine, sodium hypochloriate, 4-chlorobutanal, formylcyclopropanes, m-phenoxybenzaldehyde.
Oxetane ring enlargement through nucleophilic trapping of radical cations by acetonitrile
Perez-Ruiz, Raul,Saez, Jose A.,Domingo, Luis R.,Jimenez, M. Consuelo,Miranda, Miguel A.
, p. 5700 - 5703 (2012)
Oxidative electron transfer cycloreversion of trans,trans-2-cyclopropyl-4- methyl-3-phenyloxetane, using triphenylthiapyrylium perchlorate as a photosensitizer, leads to distonic 1,4-radical cations; subsequent cleavage gives rise to fragmentation products (pathway a), whereas nucleophilic trapping by acetonitrile affords a ring expanded oxazine (pathway b).
Kinetics of Cyclopentene Isomerization at 1200 K
Lewis, David K.,Baldwin, John E.,Cianciosi, Steven J.
, p. 7464 - 7467 (1990)
This study was conducted to determine the rate of intramolecular degenerate rearrangement of cyclopentene (CP), presumably via reversible conversion to vinylcyclopropane (VCP).Cyclopentene-3-13C was synthesized and heated to 1200 K in a single-pulse shock tube and then analyzed by 13C NMR to ascertain the extent of migration of the 13C label to the 4-position.The very small amounts of migration observed were consistent with log k (CP -> VCP) = 15.7 - (16000/T).This rate constant for CP -> VCP is too small to account for the previously reported evidence of multiple channels for H2 elimination from CP.
Method for synthesizing cyclopropanecarboxaldehyde from 1,4-butanediol
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Paragraph 0054-0058; 0064-0068, (2021/03/13)
The invention relates to a method for synthesizing cyclopropanecarboxaldehyde from 1,4-butanediol. The method has the advantages of accessible raw materials, low cost and simple technique, can implement one-step reaction, has high efficiency, and can implement continuous operation.
Thiourea-Mediated Halogenation of Alcohols
Mohite, Amar R.,Phatake, Ravindra S.,Dubey, Pooja,Agbaria, Mohamed,Shames, Alexander I.,Lemcoff, N. Gabriel,Reany, Ofer
, p. 12901 - 12911 (2020/11/26)
The halogenation of alcohols under mild conditions expedited by the presence of substoichiometric amounts of thiourea additives is presented. The amount of thiourea added dictates the pathway of the reaction, which may diverge from the desired halogenation reaction toward oxidation of the alcohol, in the absence of thiourea, or toward starting material recovery when excess thiourea is used. Both bromination and chlorination were highly efficient for primary, secondary, tertiary, and benzyl alcohols and tolerate a broad range of functional groups. Detailed electron paramagnetic resonance (EPR) studies, isotopic labeling, and other control experiments suggest a radical-based mechanism. The fact that the reaction is carried out at ambient conditions, uses ubiquitous and inexpensive reagents, boasts a wide scope, and can be made highly atom economic, makes this new methodology a very appealing option for this archetypical organic reaction.
Highly Efficient Binuclear Copper-catalyzed Oxidation of N,N-Dimethylanilines with O2
Liu, Yuxia,Yan, Yonggang,Xue, Dong,Wang, Zhongfu,Xiao, Jianliang,Wang, Chao
, p. 2221 - 2225 (2020/03/23)
A binuclear copper-salicylate complex, [Cu(Sal)2(NCMe)]2 (Sal=salicylate), was found to be an active catalyst for the oxidation of N,N-dimethylanilines by O2, affording the corresponding N-methyl-N-phenylformamides as major products. The reactions were carried out with a O2 balloon and the S/C (substrate/catalyst ratio) of the model reaction could be up to 1×105, providing a practical and highly efficient catalytic protocol for accessing N-methyl-N-phenylformamides.
