123-63-7Relevant articles and documents
Liquid Phase Reaction of Acetaldehyde over Various ZSM-5 Zeolites
Mori, Hidemitsu,Yamazaki, Tatsuya,Ozawa, Sentaro,Ogino, Yoshisada
, p. 2498 - 2504 (1993)
Acetaldehyde reacted over various ion-exchanged ZSM-5 zeolites at 15+/-0.5 deg C under a nitrogen pressure of 1x105 Pa.The main products of the reaction were 2α,4α,6α-trimethyl-1,3,5-trioxane (cis-paraldehyde) and its isomer, 2α,4α,6β-trimethyl-1,3,5-trioxane (trans-paraldehyde).Several rare earth ZSM-5 (REZSM-5) and M/HZSM-5 (partially proton exchanged ZSM-5) catalysts exhibited high activities for trans-paraldehyde formation.The reaction appeared to proceed by the following scheme: cis-paraldehyde acetaldehyde trans-paraldehyde.A comparison of the catalytic activity with the IR intensity of acidic OH groups over the catalyst suggested that the active site for cis-paraldehyde formation was the Broensted acidic site, while the active site for trans-paraldehyde formation was a Broensted acid site in the neighborhood of an Mn+ site in the ZSM-5 zeolite pore.
Hatcher,Brodie
, p. 574 (1931)
FORMATION OF THIOPHENE BY PYROLYSIS OF DIVINYL SULFOXIDE
Voronkov, M. G.,Deryagina, E. N.,Sukhomazova, E. N.,Gusarova, N. K.,Efremova, G. G.,et al.
, p. 174 - 175 (1982)
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Synthesis of antimalarial 1,2,4-trioxanes via photooxygenation of a chiral allylic alcohol
Griesbeck, Axel G.,El-Idreesy, Tamer T.,Fiege, Maren,Brun, Reto
, p. 4193 - 4195 (2002)
(equation presented) Photooxygenation of the chiral allylic alcohol 4-methyl-3-penten-2-ol (3) in nonpolar solvents and subsequent Lewis acid-catalyzed peroxyacetalization afforded a series of monocyclic and spirobicyclic 1,2,4-trioxanes (5, 6). Two products show significant anti-Malaria activity against Plasmodium falciparum when compared with chloroquine.
Acid-catalyzed trimerization of acetaldehyde: A highly selective and reversible transformation at ambient temperature in a zeolitic solid
Harris,Thomas,Lee,Sankar,Kitchin,Dugal
, p. 1322 - 1326 (2002)
Acetaldehyde underwent a reversible Bronsted acid-catalyzed cyclotrimerization reaction, with 100% selectivity, at ambient temperature within the zeolites host material ferrierite. The cyclic trimer was the only product formed in the reaction. The equilibrium proportions of acetaldehyde and the cyclic trimer at ambient temperature corresponded to a conversion > 90%. On the contrary, a broad distribution of products was obtained in the corresponding acid-catalyzed transformation of acetaldehyde in the liquid state. The reversibility of the cyclotrimerization reaction in ferrierite was confirmed from the fact that, on adsorption of a pure sample of the cyclic trimer within ferrierite, a reaction occurred to produce acetaldehyde as the only product with the same equilibrium distribution of the cyclic trimer and acetaldehyde as that realized from the reaction of acetaldehyde in ferrierite. The fact that no reaction occurred on adsorption of acetaldehyde within sodium-exchanged ferrierite confirmed the role of Bronsted acid catalysis in the transformation between acetaldehyde and the cyclic trimer in ferrierite.
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Hantzsch,Oechslin
, p. 4341 (1907)
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SELECTIVE REMOVAL OF IMPURITIES IN ACETIC ACID PRODUCTION PROCESSES
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Paragraph 0091, (2017/07/18)
Processes for producing carboxylic acid are included herein. The processes include contacting methanol and carbon monoxide in the presence of a liquid reaction medium under carbonylation conditions sufficient to form a carbonylation product including acetic acid and one or more components selected from acetaldehyde, formic acid and combinations thereof, wherein the liquid reaction medium includes: a carbonylation catalyst selected from rhodium catalysts, iridium catalysts and palladium catalysts; and water in a water concentration in a range of 1 wt.% to 14 wt.% based on the total w eight of the liquid reaction medium; and contacting at least a portion of the carbonylation product or a derivative thereof with an adsorbent at adsorption conditions sufficient to selectively reduce a concentration of one or more components present in the carbonylation product, wherein the adsorbent includes a silicoaluminophosphate (SAPO).
Paraldehyde preparation method
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Paragraph 0012, (2016/10/08)
The present invention discloses a paraldehyde preparation method, which comprises: 1, adding a copper-based salt to ethanol to make the ethanol be subjected to a dehydrogenation reaction so as to obtain acetaldehyde; and 2, adding the prepared acetaldehyde to an enamel reaction pot while adding a catalyst calcium chloride to make the acetaldehyde be subjected to a polymerization reaction so as to generate the paraldehyde, wherein the polymerization reaction is performed for 14 h at a temperature of 30-35 DEG C under the effect of external circulation freezing water. According to the present invention, the paraldehyde yield is improved; the requirement on the reactor compression resistance is reduced so as to reduce the enterprise production cost; copper acetate is adopted as the precursor for producing the copper active ingredient, the selectivity of the catalytic activity is good, and the yield of the obtained paraldehyde is high; and the single food-grade ethanol is adopted as the production raw material, the whole production process is environmental pollution and pollution-free, and the sustainable ecology development is easily achieved.