- Method for copper-catalyzed carboxylation reaction of arylboronic acid and carbon dioxide
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The invention discloses a method for a copper-catalyzed carboxylation reaction of arylboronic acid and carbon dioxide. According to the method, carbon dioxide is used as a C1 source, copper catalysisis adopted, alkoxide serves as alkali, and a reaction is carried out in an organic solvent; the method is simple in process and easy to implement, and shows wide functional group compatibility; the method allows various arylboronic acids such as monosubstituted or polysubstituted phenylboronic acid, polycyclic aromatic hydrocarbon boronic acid and benzoheterocyclic boronic acid to be converted into corresponding arylcarboxylic acids with considerable yield under mild conditions; and the produced carboxylic acids have important application value, and can be used for deriving a great number of other common chemical substances, such as acyl halide, acid anhydride, ester and amide.
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Paragraph 0079; 0080
(2019/12/29)
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- Production of Terephthalic Acid from Corn Stover Lignin
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Funneling and functionalization of a mixture of lignin-derived monomers into a single high-value chemical is fascinating. Reported herein is a three-step strategy for the production of terephthalic acid (TPA) from lignin-derived monomer mixtures, in which redundant, non-uniform substitutes such as methoxy groups are removed and the desired carboxy groups are introduced. This strategy begins with the hydro-treatment of corn-stover-derived lignin oil over a supported molybdenum catalyst to selectively remove methoxy groups. The generated 4-alkylphenols are converted into 4-alkylbenzoic acids by carbonylation with carbon monoxide. The Co-Mn-Br catalyst then oxidizes various alkyl chains into carboxy groups, transforming the 4-alkylbenzoic acid mixture into a single product: TPA. For this route, the overall yields of TPA based on lignin content of corn stover could reach 15.5 wt %, and importantly, TPA with greater than 99 % purity was obtained simply by first decanting the reaction mixture and then washing the solid product with water.
- Song, Song,Zhang, Jiaguang,G?zayd?n, G?kalp,Yan, Ning
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supporting information
p. 4934 - 4937
(2019/02/24)
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- Electrophilicity and nucleophilicity of commonly used aldehydes
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The present approach for determining the electrophilicity (E) and nucleophilicity (N) of aldehydes includes a kinetic study of KMNO4 oxidation and NaBH4 reduction of aldehydes. A transition state analysis of the KMNO4 promoted aldehyde oxidation reaction has been performed, which shows a very good correlation with experimental results. The validity of the experimental method has been tested using the experimental activation parameters of the two reactions. The utility of the present approach is further demonstrated by the theoretical versus experimental relationship, which provides easy access to E and N values for various aldehydes and offers an at-a-glance assessment of the chemical reactivity of aldehydes in various reactions. the Partner Organisations 2014.
- Pratihar, Sanjay
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p. 5781 - 5788
(2014/07/22)
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- Inclusion complex containing epoxy resin composition for semiconductor encapsulation
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The invention is an epoxy resin composition for sealing a semiconductor, including (A) an epoxy resin and (B) a clathrate complex. The clathrate complex is one of (b1) an aromatic carboxylic acid compound, and (b2) at least one imidazole compound represented by formula (II): wherein R2 represents a hydrogen atom, C1-C10 alkyl group, phenyl group, benzyl group or cyanoethyl group, and R3 to R5 represent a hydrogen atom, nitro group, halogen atom, C1-C20 alkyl group, phenyl group, benzyl group, hydroxymethyl group or C1-C20 acyl group. The composition has improved storage stability, retains flowability when sealing, and achieves an effective curing rate applicable for sealing delicate semiconductors.
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- An efficient approach for the deprotection of esters using ionic liquid as nucleophile
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An efficient approach for the deprotection of esters has been developed using ionic liquid as nucleophile in the presence of protic acid. Using methyl benzoate as a model compound, the best result was obtained by the combination of 1-methylimidazolium bromide and methane sulfonic acid with a conversion of 96 % after 2 h at 120 C.
- Wei, Benmei,Zhang, Zhiyong,Dai, Zhiqun,Guan, Jintao
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p. 6404 - 6406
(2013/07/26)
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- INHIBITORS OF STEAROYL-COA DESATURASE
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Provided herein are compounds of the formula (I): as well as pharmaceutically acceptable salts thereof, wherein the substituents are as those disclosed in the specification. These compounds, and the pharmaceutical compositions containing them, are useful for the treatment of diseases such as, for example, obesity.
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- Liquid crystal compounds
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A liquid crystal compound having the formula: STR1 where X is --CH2.CH2 -- or CH2 O Y is STR2 and R is a straight or branched (possibly chiral) alkyl group having up to 15 carbon atoms.
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- Cyano-substituted biphenyl compounds and liquid crystalline dielectrics containing the same
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Biphenyl derivatives of the formula: STR1 wherein X is --CO--O-- or --O--CO--, R1 and R4 are alkyl of 1 to 10 carbon atoms, and one of R2 and R3 is CN and the other is H, are useful for lowering the dielectric anisotropy of liquid crystalline dielectrics.
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