4740-79-8Relevant academic research and scientific papers
Method for preparing ketal glycerine and/or acetal glycerine by catalyzing glycerine
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Paragraph 0178-0179; 0193, (2020/07/02)
The invention relates to a method for preparing ketal glycerine and/or acetal glycerine by catalyzing glycerine. The method comprises the following steps: contacting glycerine and a reaction raw material with a catalyst in a reactor, and reacting to obtain a product containing ketal glycerine and/or acetal glycerine, wherein the reaction raw materials contains aldehyde and/or ketone, the molar ratio of glycerine to aldehyde and/or ketone is 1:(1-10), the reaction temperature is 30-180 DEG C, the reaction time is 1-10 hours, the catalyst contains a tin-silicon molecular sieve, and the weight ratio of glycerine to the tin-silicon molecular sieve based on dry basis weight is (1-40):1, the tin-silicon molecular sieve contains a silicon element, a tin element and an oxygen element, a cavity orcavity structure is formed in all or part of crystal grains, the total specific surface area is larger than or equal to 300 m/g, and the proportion of the external specific surface area to the total specific surface area is larger than or equal to 10%. The method provided by the invention has high aldehyde/ketone conversion rate and high acetal/ketal glycerine selectivity.
New technology for synthesizing 1,3-propylene glycol from glycerin through dehydroxylation method
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Paragraph 0032; 0033; 0034; 0035, (2017/05/12)
The invention discloses a new technology for synthesizing 1,3-propylene glycol from glycerin through a dehydroxylation method. The technology comprises the following steps: protecting two hydroxyl groups at the head end and the tail end of a glycerin molecule through using a group protection process, converting a hydroxyl group in the middle of the molecule into a group easy to eliminate, that is a sulfonyloxy group, removing hydroxyl group protection groups, and reducing the sulfonyloxy in the presence of a catalyst in order to obtain the 1,3-propylene glycol product. The technology has the characteristics of few byproducts, easiness in separation, and low cost, is a route with environmentally-friendly and economic dual values, and has wide development prospect.
Aromatic Monomers by in Situ Conversion of Reactive Intermediates in the Acid-Catalyzed Depolymerization of Lignin
Deuss, Peter J.,Scott, Martin,Tran, Fanny,Westwood, Nicholas J.,De Vries, Johannes G.,Barta, Katalin
supporting information, p. 7456 - 7467 (2015/06/30)
Conversion of lignin into well-defined aromatic chemicals is a highly attractive goal but is often hampered by recondensation of the formed fragments, especially in acidolysis. Here, we describe new strategies that markedly suppress such undesired pathways to result in diverse aromatic compounds previously not systematically targeted from lignin. Model studies established that a catalytic amount of triflic acid is very effective in cleaving the β-O-4 linkage, most abundant in lignin. An aldehyde product was identified as the main cause of side reactions under cleavage conditions. Capturing this unstable compound by reaction with diols and by in situ catalytic hydrogenation or decarbonylation lead to three distinct groups of aromatic compounds in high yields acetals, ethanol and ethyl aromatics, and methyl aromatics. Notably, the same product groups were obtained when these approaches were successfully extended to lignin. In addition, the formation of higher molecular weight side products was markedly suppressed, indicating that the aldehyde intermediates play a significant role in these processes. The described strategy has the potential to be generally applicable for the production of interesting aromatic compounds from lignin.
Clay catalysed rapid valorization of glycerol towards cyclic acetals and ketals
Pawar, Radheshyam R.,Gosai, Kalpeshgiri A.,Bhatt, Adarsh S.,Kumaresan,Lee, Seung Mok,Bajaj, Hari C.
, p. 83985 - 83996 (2015/10/28)
Biodiesel production usually results in a huge amount of glycerol, raising a critical need to transform it into high value products. The present study highlights that solvent-free, conventional thermal activation, and non-conventional microwave/ultrasonic activation in the liquid phase are able to selectively transform glycerol into cyclic acetals and ketals using an optimised acid activated clay catalyst. Several parameters for the acid activation of bentonite clay were optimized under mild reaction conditions with a high concentration of clay (6%) and varying the acid concentration in the range of 6 to 15 N. The acid-activated clay samples were characterized by XRD, FT-IR, BET, and XRF analysis. The active sites of the catalyst were examined by volumetric titration and confirmed by pyridine adsorbed FT-IR and advanced NH3-TPD analyses. The activation performed at relatively mild conditions, i.e.; 6 N H2SO4 and 6% w/v clay, reproducibly resulted in an improved surface area (180 m2 g-1) and surface acidity (23 mg KOH g-1), with superior quantitative Br?nsted and Lewis acidic sites. Moreover, the eco-friendly process involving a catalyst, microwave, or ultra-sonication were successfully utilized to achieve a commercially valuable hyacinth fragrance, in addition to furan-based fuel additive precursors exhibiting a high conversion of glycerol and excellent selectivity within much less activation time (2 min).
NUCLEOPHILIC ADDITION TO ALKYNES IN SUPERBASIC CATALYTIC SYSTEMS. IV. VINYLATION OF ALCOHOLS BY PHENYLACETYLENE. A PATH TO PHENYLACETALDEHYDE AND ITS ACETALS
Tarasova, O. A.,Mikhailova, A. I.,Shmidt, E. Yu.,Polovnikova, R. I.,Trofimov, B. A.
, p. 860 - 862 (2007/10/02)
A method is proposed for the synthesis of phenylacetaldehyde, involving nucleophilic addition of methanol to phenylacetylene in the potassium hydroxide-DMSO system followed by acid-catalyzed hydrolysis of the obtained methyl styryl ether.Electrophilic addition of alcohols and glycerol to the latter in the presence of p-toluenesulfonic acid leads to high yields of the corresponding acetals of phenylacetaldehyde.
