Abstract: A method for purifying a crude 2,5-furandicarboxylic acid composition including 2,5-furandicarboxylic acid and 2-furoic acid is disclosed. The method includes the steps of: (a) mixing the crude 2,5-furandicarboxylic acid composition with a solvent solution that includes alcohol so as to obtain a mixture; (b) heating the mixture to permit full dissolution of the crude 2,5-furandicarboxylic acid composition in the solvent solution; and (c) cooling the mixture to permit recrystallization of the 2,5-furandicarboxylic acid from the mixture so as to obtain purified 2,5-furandicarboxylic acid.

Abstract: A method for purifying a crude 2,5-furandicarboxylic acid composition including 2,5-furandicarboxylic acid and 2-furoic acid is disclosed. The method includes the steps of: (a) mixing the crude 2,5-furandicarboxylic acid composition with a solvent solution that includes alcohol so as to obtain a mixture; (b) heating the mixture to permit full dissolution of the crude 2,5-furandicarboxylic acid composition in the solvent solution; and (c) cooling the mixture to permit recrystallization of the 2,5-furandicarboxylic acid from the mixture so as to obtain purified 2,5-furandicarboxylic acid.

Abstract: A method for purifying a crude 2,5-furandicarboxylic acid composition including 2,5-furandicarboxylic acid and 5-formylfuran-2-carboxylic acid is disclosed. The method includes the steps of: (a) subjecting the crude 2,5-furandicarboxylic acid composition to complete dissolution in a solvent solution to obtain a mixture, the solvent solution including an organic solvent and water; (b) subjecting 5-formylfuran-2-carboxylic acid in the mixture to an addition reaction with sodium hydrogen sulfite to obtain an addition product; and (c) subjecting 2,5-furandicarboxylic acid to precipitation after step (b) to obtain purified 2,5-furandicarboxylic acid.

Abstract: A process for preparing 2,5-furandicarboxylic acid includes the steps of: subjecting an 5-acyloxymethyl-furfural compound to an oxidation reaction with an oxygen-containing gas in the presence of a basic aqueous solution and an oxidation catalyst containing a metal selected from the group consisting of ruthenium, rhodium, palladium, and combinations thereof to form an aqueous solution containing 2,5-furandicarboxylate, and converting the 2,5-furandicarboxylate to 2,5-furandicarboxylic acid.

Abstract: A method for producing alkyl substituted benzene includes (a) providing a starting material selecting from the group consisting of furan, an alkyl substituted furan, 2-methylfuran, 2,3-dimethylfuran, 2,4-dimethylfuran, 2,5-dimethylfuran, 2,5-hexanedione, and combinations thereof, and (b) subjecting the starting material to a cycloaddition reaction with a monoene in the absence of solvent and in the presence of the metal triflate catalyst to produce an alkyl substituted benzene.

Abstract: Disclosed herein is a process for preparing 5-(chloromethyl)furfural which includes the steps of: subjecting a cellulosic biomass to a pretreatment so as to obtain a pretreated cellulosic biomass, the pretreatment including a dilute acid treatment and a steam explosion treatment conducted after the dilute acid treatment; mixing the pretreated cellulosic biomass with hydrochloric acid so as to obtain a mixture; reacting the pretreated cellulosic biomass with the hydrochloric acid in the mixture so as to produce a reaction product containing 5-(chloromethyl) furfural; and extracting 5-(chloromethyl)furfural from the reaction product with an organic solvent.

Abstract: A method for producing terephthalic acid comprises the steps of: subjecting methyl acrylate to contact with aluminum chloride so as to form a complex; adding isoprene to the complex to result in a Diels-Alder reaction which is kept at a temperature no higher than 50° C. by cooling so as to obtain a cyclic adduct product; subjecting the cyclic adduct product to separation so as to obtain a cyclic para-precursor; and subjecting the cyclic para-precursor to a chemical reaction so as to obtain terephthalic acid.

Abstract: Orthogonally protected disaccharide building blocks for synthesis of heparin saccharide are disclosed. The disaccharide building block has a formula (I), in which L is a leaving group, P1, P2, P3 and P4 are different, and of them P1 is an ester-type protecting group, P2 is a hydroxyl protecting group that could be oxidized to a carboxylic acid, P3 is a hydroxyl protecting group, and P4 is a hydroxyl protecting group which allows chemoselective deprotection with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ). Acting as an elongation unit, the disaccharide building block of formula (I) may react with a starting unit of formula (II) to synthesize a heparin saccharide of desired size.

Abstract: Orthogonally protected disaccharide building blocks for synthesis of heparin oligosaccharide. The disaccharide building block has a formula (I), in which L is a leaving group, P1, P2, P3 and are different, and of them P1 is an ester-type protecting group, P2 is a hydroxyl protecting group that could be oxidized to a carboxylic acid, P3 is a hydroxyl protecting group, and P4 is a hydroxyl protecting group which allows chemoslective deprotection with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ). Acting as an elongation unit, the disaccharide building block of formula (I) may react with a starting unit of formula (II) to synthesize a heparin oligosaccharide.

Abstract: The present invention provides composition and methods for the synthesis of low molecular weight heparins and heparinoids. The present invention also provides compositions having substantially homogenous populations of desired heparin molecules, or molecules useful in the synthesis of heparin oligosaccharides.

Abstract: The present invention provides composition and methods for the synthesis of low molecular weight heparins and heparinoids. The present invention also provides compositions having substantially homogenous populations of desired heparin molecules, or molecules useful in the synthesis of heparin oligosaccharides.