25260-60-0Relevant articles and documents
Ionic liquid [BMIM]PF6 as a medium for the selective hydrogenation of 1,4-diacetoxybut-2-yne on the Pd-containing catalysts
Tarasenko,Isaeva,Beletskaya,Kustov
, p. 179 - 181 (2011)
A possibility of using a ionic liquid, 1-n-butyl-3-methylimidazolium hexafluorophosphate ([BMIM]PF6), as a reaction medium in the liquid-phase hydrogenation of 1,4-diacetoxybut-2-yne was examined. Two types of catalysts were studied: Pd(10%)/C and the palladium-containing catalytic system based on the biopolymer chitosan supported on silica gel (Pd(1%)/chitosan/SiO2). The data obtained indicate high selectivity of hydrogenation of 1,4-diacetoxybut-2-yne to cis-1,4-diacetoxybut-2-ene under selected conditions.
Preparation method of 4-acetoxy-2-methyl-2-butenal
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Paragraph 0064-0067, (2021/08/11)
The invention discloses a method for preparing 4-acetoxyl-2-methyl-2-butenal, and the method comprises the following steps: forming a catalyst system by using a cobalt acid complex and a metal chloride, mixing 4-acetoxyl-2-methylene butyraldehyde (III) with hydrogen, and performing heating to react to obtain the 4-acetoxyl-2-methyl-2-butenal. In the prior art, precious metal needs to be used as a catalyst in the step, and the yield and the selectivity are not high. The method does not need to use a noble metal catalyst, is lower in cost, high in double-bond isomerization reaction speed and high in reaction yield, and is easy to realize industrial production.
Process for preparation of 4-acetoxy-2-methyl-2-butene-1-aldehyde and intermediates thereof
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Paragraph 0055-0056; 0065-0066; 0072-0073; 0079-0080, (2021/06/09)
The invention relates to the technical field of organic synthesis, and discloses a method for preparing 4-acetoxy-2-methyl-2-butene-1-aldehyde and an intermediate thereof. The method comprises the following steps: (1) in the presence of an esterification reagent, carrying out esterification reaction on 1, 4-butenediol to obtain 1, 4-butenediol diacetate; (2) in the optional presence of a first catalyst, carrying out an isomerization reaction on the 1, 4-butenediol diacetate to obtain 3, 4-diacetoxy-1-butene; (3) in the presence of a phosphorus-containing ligand and a rhodium catalyst and/or a cobalt catalyst, carrying out hydroformylation reaction on the 3, 4-diacetoxy-1-butene, carbon monoxide and hydrogen to obtain 2-methyl-3, 4-diacetoxy-1-butyraldehyde; (4) in the optional presence of a third catalyst, carrying out an elimination reaction on the 2-methyl-3, 4-diacetoxyl-1-butyraldehyde to obtain the 4-acetoxyl-2-methyl-2-butene-1-aldehyde. The method provided by the invention has the advantages of mild reaction conditions, environmental friendliness and high yield.
Protection of COOH and OH groups in acid, base and salt free reactions
Zhu, Xiaotao,Qian, Bo,Wei, Rongbiao,Huang, Jian-Dong,Bao, Hongli
supporting information, p. 1444 - 1447 (2018/04/12)
We report an iron-catalyzed general functional group protection method with inexpensive reagents. This environmentally benign process does not use acids or bases, and does not produce waste products. Further purification beyond filtration and evaporation is, in most cases, unnecessary. Free COOH and OH groups can be protected in a one-pot reaction.
Preparation method of 3,4-diacetoxy-1-butene
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Paragraph 0039; 0052; 0058; 0064; 0074-0077, (2018/04/01)
The invention discloses a preparation method of 3,4-diacetoxy-1-butene. The preparation method comprises steps as follows: an esterification step: 1,4-butylene glycol and acetic acid are subjected to an esterification reaction in the presence of acid, a solution containing 1,4-diacetoxy-2-butene and acetic acid is obtained, acetic acid is removed and 1,4-diacetoxy-2-butene is obtained; an isomerization step: cuprous catalysts are added to 1,4-diacetoxy-2-butene obtained in the esterification step, the mixture is heated for an isomerization rearrangement reaction, and a mixed solution containing 3,4-diacetoxy-1-butene is obtained; a purification step: the mixed solution obtained in the isomerization step is purified, and 3,4-diacetoxy-1-butene is obtained. The preparation method adopts easy-to-realize reaction conditions and has the characteristic of high yield.
Allylic C–H acetoxylation of terminal alkenes over TiO2 supported palladium nanoparticles using molecular oxygen as the oxidant
Zhang, Zhenzhong,Wu, Qixun,Hashiguchi, Taishin,Ishida, Tamao,Murayama, Haruno,Tokunaga, Makoto
, p. 18 - 22 (2016/09/02)
A method for synthesizing linear allylic acetates from terminal alkenes over TiO2 supported Pd nanoparticles (NPs) has been developed, in which O2 serves as the sole oxidant. Good catalytic activity was performed when using allylbenzene as a substrate and the catalyst can be reused at least five times without activity losing. The catalytic system has a broad substrate scope including transformation of 1,3-butadiene into 1,4-diacetoxy-2-butene, which is an important industrial intermediate for production of 1,4-butanediol. In contrast to previous reports that the Pd-catalyzed allylic acetoxylation is generally promoted by PdII species, the XAFS measurements suggest that this reaction is catalyzed over Pd0 NPs. Additionally, XPS analysis of the catalyst confirms the interaction between Pd and TiO2, which probably promote the initial catalytic procedure.
Comparison of reactivity in the cross metathesis of allyl acetate-derivatives with oleochemical compounds
Behr, Arno,Toepell, Stephanie
, p. 603 - 611 (2015/03/04)
The metathesis of unsaturated oleochemicals is an excellent tool for generating α,ω-difunctional substrates, which are useful intermediates for polymer synthesis. This article describes the cross metathesis of allyl acetate and cis-1,4-diacetoxy-2-butene with methyl 10-undecenoate and methyl oleate, which are oleochemical key substrates. Detailed optimizations led to high conversion rates and yields of the desired products under mild reaction conditions by using a low concentration of commercially available homogeneous ruthenium catalysts.
METHOD FOR ISOMERIZING ALLYL COMPOUND
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Paragraph 0119; 0120, (2017/01/02)
Catalyst for isomerization of allyl compound in method, catalyst by restraining degradation caused, low catalyst levels usage in high yield isomer make it possible to obtain a an industrially advantageous method provides for isomerization of allyl compounds. In the presence of catalyst, raw material allyl compound corresponding allyl compound as isomerizing method, before isomerization using catalyst raw material allyl compounds organic phosphorus compound-containing solution is characterized by contacting the isomerization method.
Biomass derived β-cyclodextrin-SO3H as a solid acid catalyst for esterification of carboxylic acids with alcohols
Thombal, Raju S.,Jadhav, Amol R.,Jadhav, Vrushali H.
, p. 12981 - 12986 (2015/02/19)
A novel β-cyclodextrin-SO3H carbon based solid acid catalyst was prepared in a convenient and ecofriendly manner and was characterized using FTIR, PXRD, EDAX and NH3TPD to illustrate that the carbon material has been functionalized with -SO3H, -COOH and -OH groups. The catalyst was studied for esterification of various carboxylic acids and alcohols under solvent free conditions and showed excellent catalytic performance and gave good yields of esters in the range 78-99% at 70°C. No solvent was used either for catalyst preparation nor for esterification reaction. The catalyst can be easily recovered by simple filtration and reused for subsequent three runs without any significant impact on yields of products. The main advantage of this methodology is easy and ecofriendly catalyst preparation, easy catalyst separation, practical simplicity, safe reaction conditions, recyclable catalyst and high product yields.
((2S,4R)-4,6-dihydroxytetrahydro-2H-pyran-2-yl)methyl carboxylate and process for the production thereof
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Page/Page column 21, (2013/04/10)
The present invention relates to ((2S,4R)-4,6-dihydroxytetrahydro-2H-pyran-2-yl)methyl carboxylates and a process for the production thereof. Furthermore, the present invention relates to a process for the production of statins and in particular of Rosuvastatin and derivates thereof, wherein the above mentioned compounds are used as intermediates.