- Method for preparing olefine aldehyde through catalytic oxidation of enol ether
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The invention relates to the technical field of olefine aldehyde preparation, and provides a method for preparing olefine aldehyde through catalytic oxidation of enol ether. According to the invention, a palladium catalyst, a copper salt, a solvent and enol ether are mixed and subjected to a catalytic oxidation reaction to obtain olefine aldehyde. According to the method, the copper salt is used as the oxidizing agent, the mixed solvent of water and acetonitrile is used as the reaction solvent, and the volume ratio of water to acetonitrile in the mixed solvent is controlled to be (3-7): (3-7), so that the catalytic oxidation reaction can be smoothly carried out in the mixed solvent with a specific ratio, and the generation of palladium black precipitate can be avoided. The method provided by the invention has the advantages of simple steps, low reagent cost, no need of dangerous reagents, wide substrate adaptability and small catalyst dosage. Furthermore, octadecane mercaptan is added to promote the catalytic oxidation reaction, and when the dosage of the palladium catalyst is extremely low, the olefine aldehyde yield can be greatly increased by adding octadecane mercaptan.
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Paragraph 0082-0087
(2021/06/23)
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- Method for reducing carboxylic acid compound into aldehyde
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The invention discloses a method for reducing a carboxylic acid compound into aldehyde. In a nitrogen atmosphere, in an organic solvent, a ligand/Cu catalyst, the carboxylic acid compound, an anhydride compound and hydrosilane are added by a one-pot method, a reaction is performed under the condition of the temperature of 20-120 DEG C for 2-20 h, after the reaction is completed, quenching and column chromatography separation are performed to obtain the product. The carboxylic acid compound can be successfully converted into aldehyde through one-pot reaction, especially unsaturated carboxylic acid can be reduced, and the reaction yield is generally relatively high. Compared with the prior art, the method has the outstanding advantages that the cheap copper salt is used as a catalyst, so that the experiment cost is greatly reduced. Meanwhile, the used method enlarges the application range of the reaction substrate, improves the compatibility of functional groups, and provides a new synthesis way for reducing the carboxylic acid compound into aldehyde.
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Paragraph 0021-0031
(2020/02/27)
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- Highly efficient Au hollow nanosphere catalyzed chemo-selective oxidation of alcohols
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Micelles of poly(styrene-b-2-vinyl pyridine-b-ethylene oxide) (PS-PVP-PEO) with core-shell-corona structures have been used as a scaffold for the fabrication of gold (Au) hollow nanospheres of particle size 26 ± 2 nm using HAuCl4 and NaBH4 as metal precursor and reducing agent, respectively. The PS core acts as a template for hollow void, the PVP shell serves as reaction sites for inorganic precursors, and PEO corona stabilizes the composite particles. Under acidic conditions, the PVP shell domain becomes positively charged pyridinum-species that electrostatically interacts with negatively charged AuCl4- ions. On reduction of these composite particles and subsequent solvent extraction leads to the formation of Au hollow nanospheres. Various analytical tools such as powder X-ray diffraction (XRD), transmission electron microscope (TEM), thermogravimetric analyses (TG/DTA), dynamic light scattering of (DLS) have been employed to characterize the polymeric micelles and hollow nanoparticles. The TEM and XRD studies confirmed the formation of highly crystalline Au hollow nanospheres. The Au hollow nanosphere/H2O2 system efficiently catalyzes the chemoselective oxidation of allylic-type unsaturated alcohols into aldehydes and ketones under mild liquid-phase conditions. The versatility of present catalytic system for the oxidation of other substrates like aliphatic-, acylic-, aromatic-, and heteroaromatic alcohols to their respective keto compounds has also been reported.
- Sasidharan, Manickam,Anandhakumar, Sundaramurthy,Bhanja, Piyali,Bhaumik, Asim
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- Aerobic oxidation of primary aliphatic alcohols to aldehydes catalyzed by a palladium(II) polyoxometalate catalyst
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A hexadecyltrimethylammonium salt of a "sandwich" type polyoxometalate has been used as a ligand to attach a palladium(II) center. This Pd-POM compound was an active catalyst for the fast aerobic oxidation of alcohols. The unique property of this catalyst is its significant preference for the oxidation of primary versus secondary aliphatic alcohols. Since no kinetic isotope effect was observed for the dehydrogenation step, this may be the result of the intrinsically higher probability for oxidation of primary alcohols attenuated by steric factors as borne out by the higher reactivity of 1-octanol versus 2-ethyl-1-hexanol. The reaction is highly selective to aldehyde with little formation of carboxylic acid; autooxidation is inhibited. No base is required to activate the alcohol. The fast reactions appear to be related to the electron-acceptor nature of the polyoxometalate ligand that may also facilitate alcohol dehydrogenation in the absence of base.
- Barats, Delina,Neumann, Ronny
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scheme or table
p. 293 - 298
(2010/04/28)
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- Highly regioselective terminal alkynes hydroformylation and Pauson-Khand reaction catalysed by mesoporous organised zirconium oxide based powders
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Zirconia-silica mesoporous powders act as very efficient heterogeneous catalysts for both alkyne hydroformylation and Pauson-Khand reaction and yield regioselectivities opposite to those usually observed. The Royal Society of Chemistry 2006.
- Goettmann, Frederic,Le Floch, Pascal,Sanchez, Clement
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p. 180 - 182
(2008/02/08)
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- Synthesis of α,β-unsaturated aldehydes and methyl carboxylic esters from 2-acetylenic phenyl sulfides
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2-Alkynylthio benzenes were reduced to 2-Alkenylthio benzenes with diisobutyl aluminum hydride. Mono chlorination of these compounds with sulfuryl chloride and pyridine followed by hydrolysis, in the presence of Cu(II) salts, gave α,β-unsaturated aldehydes. 2-Alkynylthio benzenes were converted into 2-Alkynyl 1,1-bis thiobenzenes by monochlorination with sulfuryl chloride and pyridine followed by treatment with thiophenol and triethylamine. These substances were then converted to α,β-unsaturated methyl carboxylic esters by way of isomerization with sodium methoxide to the corresponding allene and treatment with hydrochloric acid and methanolysis in the presence of iodine.
- Fortes, Carlos C.,Garrote, Clevia F. D.
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p. 3917 - 3941
(2007/10/03)
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- Synthesis and Some Properties of 1-Fluoro-1-alken-3-ols
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The reduction of 1,1-difluoro-1-alken-3-ols with lithium tetrahydroaluminate is described. 1-Fluoro-1-alken-3-ols obtained can be transformed to enals or difluoromethylated allylic derivatives.
- Tellier, Frederique,Sauvetre, Raymond
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p. 4223 - 4226
(2007/10/02)
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- Synthesis of α,β-Unsaturated Aldehydes through Palladium Catalyzed Regioselective Hydrogen Migration
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Treatment of cyclic carbonate of 3-alkene-1,2-diols or 4-methylcarbonate of 2-alkene-1,4-diols with a catalytic amount of Pd(PPh3)4 in aqueous THF or AcOH gave α,β-unsaturated aldehydes in good yields.The reaction can be interpreted by the regioselective 1,4-hyrogen migration of ?-allylpalladium intermediate.
- Minami, Tatsuya,Hanaoka, Miyoji
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p. 9425 - 9428
(2007/10/02)
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- Different Rates of Geometric Isomers of Linoleate Hydroperoxide in Acid-catalyzed Decomposition
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Methyl linoleate hydroperoxide was decomposed with 0.1M HCl in acetone-water (9:1, v/v) at 30 deg C.The decrease in four isomers of the hydroperoxide was monitored by HPLC without any derivatization.In both isomers having 13- and 9-hydroperoxy groups, those having trans,trans dienes decomposed more rapidly than those having cis,trans dienes.In all the isomers, the rates of decomposition were first order with respect to concentrations of the hydroperoxides.The yields of 2-nonenal and 12-oxo-10-dodecenoate were also measured by GC-MS. 12-Oxo-10-dodecenoate was produced only from the 13-isomers and 2-nonenal from the 9-isomers.The rapid decomposition of the trans,trans isomers didn't seem to be responsible for the formation of these aldehyde products.
- Tokita, Masako,Morita, Makio
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p. 3545 - 3550
(2007/10/02)
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