107-89-1Relevant articles and documents
Online ATR-IR investigations and mechanistic understanding of the carbonylation of epoxides - The selective synthesis of lactones or polyesters from epoxides and CO
Allmendinger, Markus,Zintl, Manuela,Eberhardt, Robert,Luinstra, Gerrit A.,Molnar, Ferenc,Rieger, Bernhard
, p. 971 - 979 (2004)
In situ ATR-IR spectroscopy is applied as a powerful tool to study the factors that control the reaction of epoxides with carbon monoxide in the presence of [Lewis acid]+ [Co(CO)4]- salts. Based on these investigations, a consistent mechanistic scheme is presented, comprising the main lactone and polyester products and minor components, e.g., acetone and crotonic acid derivatives. β-Alkoxy-acyl-cobalttetracarbonyl species are shown to be key intermediates from which two reaction routes start in dependence of the applied Lewis acid (LA). Labile LA-alkoxy combinations favor a backbiting process of the oxygen function on the Co-acyl bond, primarily producing lactone products. More stable LA-alkoxy entities are unreactive toward PO conversion and afford a polymerization reaction after the addition of a nucleophile. In that case, the Lewis acid remains bonded to the chain end.
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Broche,Gilbert
, p. 131 (1955)
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Acid-Catalyzed Enolization and Aldol Condensation of Acetaldehyde
Baigrie, Lynn M.,Cox, Robin A.,Slebocka-Tilk, Henryka,Tencer, Michal,Tidwell, Thomas T.
, p. 3640 - 3645 (1985)
The condensation of acetaldehyde (1) to an equilibrium mixture of aldol (2) and crotonaldehyde (3) is second order in 1.An excess acidity analysis reveals that a water molecule is also involved in the rate-limiting step; the reaction is actually the base-assisted addition of vinyl alcohol to protonated 1, even in concentrated H2SO4.A previous report of a kinetically first-order conversion of 1 to 3 is shown to be due to the presence of a fast-reacting oligomer of 1.The reaction of 1 in D2SO4 leads to partially deuterated 3, a result ascribed to partial conversion of vinyl alcohol to deuterated 1.Hydrogen isotop exchange of 3 was also observed, but at a slower rate.The rates of enolization of 1 were studied by iodination and are consistent with previous results and the proposed mechanism.The interconversion of 2 and 3 is shown to proceed via the enol of 2; in this case the rate-limiting step is water attack on/water loss from protonated 3/2, not proton transfer at carbon.
Chemoselective Oxidation of the Primary Alcohol Function of Diols Catalyzed by Zirconocene Complexes
Nakano, Tatsuya,Terada, Takanobu,Ishii, Yasutaka,Ogawa, Masaya
, p. 774 - 776 (1986)
Zirconocene complexes, Cp2ZrH2 and Cp2Zr2, catalyze the Oppenauer-type oxidation of alcohol functions to the corresponding carbonyl compounds in the presence of an appropriate hydrogen acceptor such as benzophenone.In the oxidation of primary α,ω-diols and of diols containing two secondary alcohol functions, one of the alcohol functions is selectively oxidized to form hydroxy aldehydes and hydroxy ketones, respectively, in substantial yields.The chemoselective oxidation of the primary alcohol function can be achieved in the oxidation of diols containing both the primary and secondary alcohol functions.
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Cookson,Trevett
, p. 3121,3129 (1956)
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Oxidation of Olefins by Palladium(II). 12. Product Distributions and Kinetics of the Oxidation of 3-Buten-2-ol and 2-Buten-1-ol by PdCl42- in Aqueous Solution
Zaw, Kyaw,Henry, Patrick M.
, p. 1842 - 1847 (1990)
The rate expression for oxidation of both allyl alcohols was determined to be rate = k2->/+>->2, an expression identical in form with that found previously for the oxidation of ethene, allyl alcohol, and other acyclic olefins, indicating similar mechanisms.Contrary to previous reports, the product distribution from 3-buten-2-ol (6) was completely different from that for 2-buten-1-ol (7), indicating that fast isomerization into an equilibrium mixture before oxidation was not occuring.A short study of the rate of isomerization using deuteriated 6 and 7 confirmed that isomerization was slow under the oxidation conditions.The distributions gave considerable information on the effects of steric and electronic factors on the modes of hydroxypalladation.While allyl alcohol gave a 3/1 preference for addition of the Pd(II) to the center carbon due to the directing influence of the hydroxyl group, 6 gave 4/1 preference for addition of Pd(II) to the end carbon.The steric effect of the methyl is thus appreciable.With 7 the double bond is internal so steric factors are not important and the directing influence of the hydroxyl will be the important effect.The ratio of Pd(II) addition next to the carbon containing the hydroxyl group to addition to the other side of the double bond is 34/1, indicating considerable directing influence of the hydroxyl.The preference for secondary over primary hydride shift is 1.25, a value which indicates almost no carbonium ion character and considerable Pd(II)-H character.Using a specifically deuterated 7, the value of the deuterium isotope effect, kH/kD, can be determined by internal competitive hydride transfer by taking into account the positional preferance for secondary hydride shift.This value of 2.2 is close to values previously determined for ethene and allyl alcohol.
Exploring the biocatalytic scope of alditol oxidase from Streptomyces coelicolor
Van Hellemond, Erik W.,Vermote, Linda,Koolen, Wilma,Sonke, Theo,Zandvoort, Ellen,Heuts, Dominic P. H. M.,Janssen, Dick B.,Fraaije, Marco W.
, p. 1523 - 1530 (2009)
The substrate scope of the flavoprotein alditol oxidase (AldO) from Streptomyces coelicolor A3(2), recombinantly produced in Escherichia coli, was explored. While it has been established that AldO efficiently oxidizes alditols to D-aldoses, this study revealed that the enzyme is also active with a broad range of aliphatic and aromatic alcohols. Alcohols containing hydroxy groups at the C-1 and C-2 positions like 1,2,4-butanetriol (Km=170 mM, k cat -4.4s-1), 1,2-pentanediol (Km=52 mM, k cat=0.85 s-1) and 1,2-hexanediol (Km=97 mM, kcat=2.0s-1) were readily accepted by AldO. Furthermore, the enzyme was highly enantioselective for the oxidation of 1,2-diols [e.g., for l-phenyl-1,2-ethanediol the (R)-enantiomer was preferred with an Is-value of 74]. For several diols the oxidation products were determined by GC-MS and NMR. Interestingly, for all tested 1,2-diols the products were found to be the a-hydroxy acids instead of the expected α-hydroxy aldehydes. Incubation of (R)-1-phenyl-1,2-ethanediol with 18O-labelled water (H 218O) revealed that a second enzymatic oxidation step occurs via the hydrate product intermediate. The relaxed substrate specificity, excellent enantioselectivity, and independence of coenzymes make AldO an attractive enzyme for the preparation of optically pure 1,2-diols and α-hydroxy acids.
IR spectral evidence of aldol condensation: Acetaldehyde adsorption over TiO2 surface
Singh, Manishwar,Zhou, Nanjia,Paul, Dilip K.,Klabunde, Kenneth J.
, p. 371 - 379 (2008)
The adsorption of acetaldehyde on particulate TiO2 surfaces has been studied at 233 K by FT-IR spectroscopy using a specially designed IR cell. It has been found that acetaldehyde initially adsorbs onto the surface through hydrogen bonding and Lewis acid sites. As the temperature is raised to 251 K, the spectroscopic evidence of formation of 3-hydroxybutanal surface intermediate is observed during aldol condensation reaction. The presence of this transient species has been characterized by the infrared features at 3185 cm-1-ν(OH), 1334 cm-1-δ(CH), 1273 cm-1-δ(COH), and 1105 cm-1-ν(C{single bond}C) and δ(COH). The assignments of all surface species are confirmed by adsorbing pure 3-hydroxybutanal and 2-butenal on TiO2 surface. A reaction mechanism consistent with the detectable surface intermediates is proposed.
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Yokokawa et al.
, p. 677 (1964)
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Schilow
, (1935)
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Preparation method of 1,3-butanediol
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Paragraph 0074; 0075; 0076, (2020/03/05)
The invention provides a preparation method of 1,3-butanediol, which comprises the following steps: acetaldehyde condensation, hydrogenation and separation. In the hydrogenation step, the purity of the prepared 1,3-butanediol is greater than 99.5% by adopting methods of staged hydrogenation, addition of a modifier into a hydrogenation catalyst and the like, the content of 1,3-dioxane impurity canbe reduced to 0.01 wt% or below, and the product is odorless. The method has the advantages of simple process, low energy consumption, simple operation, high yield and selectivity of 1,3-butanediol, high purity of 1,3-butanediol and the like, and odorless 1,3-butanediol can be obtained.
Preparation method of 1, 3-butylene glycol
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Paragraph 0033-0037; 0044-0049; 0055-0060; 0066-0069, (2019/03/26)
The invention provides a preparation method of 1, 3-butylene glycol. The preparation method comprises following steps: A, acetaldehyde is introduced into a fixed bed reactor, under the effect of a supported type solid basic catalyst, aldol condensation reaction is carried out so as to obtain 3-hydroxybutyraldehyde; and B, 3-hydroxybutyraldehyde is subjected to continuous hydrogenation reaction inthe fixed bed reactor so as to obtain 1, 3-butylene glycol. According to the preparation method, the fixed bed reactor is adopted, at the same time, the supported type solid basic catalyst is adoptedto replace a conventional liquid alkali (such as sodium hydroxide) catalysts, and in the step of hydrogenation reduction, a supported nickel hydrogenation catalyst is adopted. The preparation method is capable of solving problems in the prior art product quality is poor, product yield is low, technology process is complex, and a large amount of waste water and waste residue is generated; aldol condensation quenching step is avoided; side reactions are reduced; relatively high reaction conversion rate and yield are achieved; no neutralizing or desalting process is needed in reaction process; and great improvement of traditional 1, 3-butylene glycol preparation technology is realized.
METHODS AND HOST CELLS FOR ENHANCING PRODUCTION OF 1, 3-BUTANEDIOL
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Paragraph 0138-0141, (2017/01/31)
This application describes non-naturally occurring host cells for enhanced 1,3-butanediol (1,3-BDO) production, methods for producing 1,3-BDO using such non-naturally occurring host cells, and 1,3-BDO products produced by such non-naturally occurring host cells and methods.
