Abstract:
A method for alkylation of an anhydrosugar compound in which a dialkyl carbonate is reacted with an anhydrosugar compound in the presence of a solid phase basic catalyst. A typical anhydrosugar compound is anhydrosugar alcohol, a dianhydromonoether and mixtures thereof. The reaction step uses zeolyte as the solid phase basic catalyst. The zeolite catalyst is typically a zeolite having ammonium groups. The reaction is carried out at a temperature below 240° C and the reaction time is 2 hours or less.
Abstract:
The present application discloses: A method for the preparation of 2,5-(hydroxymethyl)furaldehyde from fructose with specific organic solvents. A method for the preparation of 2,5-(hydroxymethyl)furaldehyde from fructose with an acid catalyst. A method for the preparation of 2,5-(hydroxymethyl)furaldehyde from fructose with a with a two-phase organic solvent system. A method for the preparation of a 2,5-(hydroxymethyl)furaldehyde derivative from fructose. A method for the preparation of levulinic acid from fructose. A method for the preparation of 2,5-bis-(hydroxymethyl)furan from 2,5-(hydroxymethyl)furaldehyde.
Abstract:
Methods for the production of dehydrated sugars and derivatives of dehydrated sugars using microwave (MW) irradiation and methods of purifying the same are described. The dehydrated sugars derivatives include 5-hydroxymethyl-2-furfural (HMF) and anhydrosugar alcohols such as sorbitans and isosorbide. The derivatives include HMF ethers, levulinic acid esters, and ether derivatives of the anhydrosugar alcohols. The described methods require lower reaction temperatures and shorter reaction times than similar non microwave mediated reactions known in the art. Typical reaction conditions are 120-210C, and typical reaction times are 30 minutes or less.
Abstract:
A method of producing HMF by mixing or agitating an aqueous solution of fructose and inorganic acid catalyst with a water immiscible organic solvent to form an emulsion of the aqueous and organic phases. The mixture is heated in a flow-through reactor at elevated pressures and then separated into aqueous and organic phases to obtain HMF. The aqueous phase and the organic phase are mixed with an in-line mixer prior to, preferably, immediately before addition of the biphasic reaction mixture into the reactor. After separation, HMF is recovered from the aqueous and organic phases to obtain high yields of HMF without the presence of insoluble solid impurities.
Abstract:
A method of preparing 2,5-bis(hydroxymethyl)tetrahydrofuran comprises heating a reaction mixture comprising 2,5-(hydroxymethyl)furaldehyde, an organic solvent, and a catalyst system comprising nickel and zirconium at a temperature, for a time, and at a pressure sufficient to promote reduction of the 2,5-(hydroxymethyl)furaldehyde to 2,5-bis(hydroxymethyl)tetrahydrofuran to produce a product mixture comprising 2,5-bis(hydroxymethyl)tetrahydrofuran.
Abstract:
A method for utilizing an industrially convenient fructose source for a dehydration reaction converting a carbohydrate to a furan derivative is provided. Recovery methods also are provided. Embodiments of the methods improve upon the known methods of producing furan derivatives.
Abstract:
A process is provided for the preparation of anhydrosugar alcohols. The process involves heating a sugar alcohol or a monoanhydrosugar alcohol starting material in the presence of an acid catalyst and under pressure. Optionally the resulting product is purified. Very high purities are achieved, without necessitating the use of organic solvents in the process.
Abstract:
A process is provided for the preparation of anhydrosugar alcohols. The process involves heating a sugar alcohol or a monoanhydrosugar alcohol starting material in the presence of an acid catalyst and under pressure. Optionally the resulting product is purified. Very high purities are achieved, without necessitating the use of organic solvents in the process.
Abstract:
Described herein are single step methods of making various classes of alkylamine derivatives of furan and tetrahydrofuran by simultaneous contact of a sugar with H 2 , an acid catalyst and hydrogenation catalyst in the presence of an alkylamide solvent. The hydrogenation catalyst is a heterogeneous catalyst comprising a metal selected from the group consisting of Pt, Pd, and nickel. The acid catalysts may be homogeneous mineral acid or a heterogeneous acid catalyst on substrate. In a preferred practice the two catalysts are provided on a common heterogeneous bifunctional support. Using similar combinations of acid and hydrogenation catalysts, there is also described single step methods for making furandimethanol by simultaneously contacting a hexose with the two separate catalysts in the presence of H 2 in an aprotic solvent, such as dimethylformamide. With the same catalyst system and similar reaction conditions, 2, 5 furan dialkylethers can also be made in a single step when the solvent includes an ROH alcohol.
Abstract:
A method for alkylation of an anhydrosugar compound in which a dialkyl carbonate is reacted with an anhydrosugar compound in the presence of a solid phase basic catalyst. A typical anhydrosugar compound is anhydrosugar alcohol, a dianhydromonoether and mixtures thereof. The reaction step uses zeolyte as the solid phase basic catalyst. The zeolite catalyst is typically a zeolite having ammonium groups. The reaction is carried out at a temperature below 240° C and the reaction time is 2 hours or less.