1193-79-9Relevant articles and documents
Acylation of methylfuran with Br?nsted and Lewis acid zeolites
Koehle, Maura,Zhang, Zhiqiang,Goulas, Konstantinos A.,Caratzoulas, Stavros,Vlachos, Dionisios G.,Lobo, Raul F.
, p. 90 - 101 (2018)
The acylation of methylfuran has been investigated using Br?nsted and Lewis acid zeolite catalysts. The highest reaction rate for acylation on a per gram basis is found on zeolite Beta with high aluminum content (Si/Al = 23) and the highest turnover frequency on a per metal site basis is found on zeolite Beta with low aluminum content (Si/Al = 138). Among Lewis acid zeolites, [Sn]-Beta shows higher turnover frequency than [Hf]-, [Zr]- or [Ti]-Beta. Similar apparent activation energies were found for [Al]-Beta with different Si/Al ratios and a lower apparent activation energy was found for [Sn]-Beta. Electronic structure calculations reveal that on both [Al]- and [Sn]-Beta the most favorable pathway follows the classic addition-elimination aromatic electrophilic substitution mechanism. The calculations also reveal that, on both [Al]- and [Sn]-Beta, the rate of methylfuran acylation is controlled by the dissociation of the C–O–C linkage of the anhydride while hydrogen elimination is the rate-determining step in the acylation of furan. The latter is in complete agreement with measured primary kinetic isotope effects. One remarkable and unexpected finding from our calculations is that the most favorable catalytic pathway in [Sn]-Beta involves Br?nsted acid catalysis by the silanol group of the hydrolyzed “open” site and not Lewis acid catalysis by the Sn metal center.
Optimization for catalytic performances of Hβ zeolite in the acylation of 2-methylfuran by surface modification and solvents effect
Xiong, Yuannan,Chen, Wenqi,Zeng, Aiwu
, p. 1557 - 1574 (2017)
The liquid phase acylation of 2-methylfuran with acetic anhydride over modified Hβ zeolite was first conducted in a continuous flow reactor. The deactivation of Hβ zeolites was attributed to strong adsorption of reactants or products and was verified by GC–MS and 13C MAS NMR. Deactivated zeolites can be regenerated to their original state by calcination. The acidic properties was adjusted by surface modification on Hβ, the maximum yield of 89.5?mol% and selectivity of 100?% were obtained over tartaric acid modified by Hβ. The deposition of tetraethoxysilane to silica on Hβ contributed to enhancing the catalytic stability. Combined with the results of NH3-TPD and Py-FTIR, the amount of Broensted acids played a major role on catalytic activity. A close relationship between the catalytic stability and the ratio of the amount of strong to weak acids at 1:1 was highlighted here. The solvents' effect on the catalytic performances was examined, and 1,2-dichloroethane with moderate polarity exerted a positive effect on catalytic stability.
Method for producing furandicarboxylic acid and derivatives thereof from furfural
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, (2020/06/05)
The invention discloses a method for producing furandicarboxylic acid and derivatives thereof from furfural. The method comprises the following steps: furfural is reduced to 2-methylfuran under the hydrogen condition; acetylation reaction is carried out on 2-methylfuran to obtain 5-methyl-2-acetylfuran; 5-methyl-2-acety furan reacts with ester to obtain methyl 5-methyl-2-furanformate, methyl 5-methyl-2-furanformate is oxidized into monomethyl 2,5-furandicarboxylate under the oxygen condition, and monomethyl 2,5-furandicarboxylate is hydrolyzed into monomethyl 2,5-furandicarboxylate or furtheresterified with methyl alcohol to generate dimethyl 2,5-furandicarboxylate. The cheap five-carbon furan compound furfural is used as a raw material, and the 2 5-furandicarboxylic acid and the derivatives thereof are prepared by a strategy of increasing a carbon chain, so that the cost of the raw material is greatly reduced. The product provided by the invention has high purity and can be directlyused as a polymerization monomer of PET polyester.
Cobalt-Catalyzed Oxygenation/Dearomatization of Furans
Oswald, Jonathan P.,Woerpel
, p. 9067 - 9075 (2018/05/29)
The dearomatization of aromatic compounds using cobalt(II) acetylacetonate with triplet oxygen and triethylsilane converts furans, benzofurans, pyrroles, and thiophenes to a variety of products, including lactones, silyl peroxides, and ketones.
