700 results about "Aldol condensation" patented technology

Described is a method for making a composition comprising alkanes. The composition is suitable for use as a liquid transportation fuel in general, and jet fuel in particular. The method includes dehydrating a feedstock solution comprising a carbohydrate, in the presence of an acid catalyst, to yield at least one furan derivative compound, in a reaction vessel containing a biphasic reaction medium: an aqueous reaction solution and a substantially immiscible organic extraction solution. The furan derivative compound is then subjected to a self-aldol condensation reaction or a crossed-aldol condensation reaction with another carbonyl compound to yield a beta-hydroxy carbonyl compound and/or an alpha-beta unsaturated carbonyl compound. The beta-hydroxy carbonyl and/or alpha-beta unsaturated compounds are then hydrogenated to yield a saturated or partially saturated compound, followed by hydrodeoxygenation (e.g., dehydrating and hydrogenating) of the saturated or partially saturated compound to yield a composition of matter comprising alkanes.

The invention relates to a process for producing high-quality hydrocarbon base oil particularly of biological origin. The process of the invention comprises aldol condensation, hydrodeoxygenation, and isomerization steps. Aldehydes and/or ketones, preferably of biological origin are used as the feedstock.

The invention relates to a new synthesis route of a liquid branched paraffin fuel, the method adopts a lignocellulose based platform compound as a raw material and is completely independent of fossil energy. The liquid fuel obtained by the method can be used as an aviation kerosene (or diesel) substitute or as an additive to increase the cetane number and cold resistance of fuel. The method provided by the invention includes two steps of: 1) under the promotion of a base catalyst, subjecting a lignocellulose based furfural compound (including furfural, methylfurfural or 5 hydroxymethylfurfural) and branched chain keto (including methyl isobutyl ketone, and mesityl oxide, etc.) to aldol condensation reaction so as to synthesize an oxygen-containing organic compound with a carbon chain length of 9-16; and 2) conducting hydrodeoxygenation on the aldol condensation product generated in step1 to obtain biomass aviation kerosene branched hydrocarbon with a carbon chain length of 9-16, higher energy density, stability and low freezing point.

The present invention relates to methods for use in producing epothilones and analogs and derivatives thereof. A general method according to the present invention broadly comprises performing an aldol condensation of a first compound with a second compound thereby to form a third compound selected from the formulas:

and stereoisomers thereof, and performing a macrolactonization of the third compound. The present invention also provides chemical compounds, and methods for producing such chemical compounds, that are useful in producing epothilones and analogs and derivatives thereof.

The invention provides a Cs-supported silica-based catalyst. One of SBA-15, SiO2 or silicon dioxide prepared by a silica sol method is used as a carrier, the support is selected from one of Cs salt and a mixture of Cs and modified elements, the catalyst is prepared by a dipping method, the Cs content is 0.1wt%-10wt%, and the content of the modified elements is 0-2wt%. Meanwhile, the invention further provides a preparation method of the Cs-supported silica-based catalyst and application of the Cs-supported silica-based catalyst to the process of preparing methyl acrylate by catalyzing condensation reaction of methyl acetate and a methanal gas phase. The prepared catalyst is capable of realizing the aldol condensation of the methyl acetate and the methanal gas phase under proper conditions so as to prepare the methyl acrylate, wherein the activity of the Cs/SBA-15 catalyst is higher than that of other Cs-supported silica-based catalysts, and the selectivity on the methyl acrylate is good.

A catalytic process for converting biomass-derived carbohydrates to liquid alkanes, alkenes, and/or ethers is described. The process uses combinations of self- and crossed-aldol condensation reactions, dehydration reactions, and hydrogenation reactions, over specified metal-containing catalysts, to yield alkane, alkene, and ether products from carbohydrate reactants.

The present invention relates to a method for preparing trimethylolpropane (TMP) comprising the steps of: 1) synthesizing trimethylolpropane by using n-butyl aldehyde, an aqueous solution of formaldehyde and an aqueous solution of alkali metal hydroxide through aldol condensation reaction and Cannizzaro reaction; 2) extracting trimethylolpropane from a resultant mixture of the step 1) by contacting the resultant mixture with an alcohol having 6 to 10 carbons; 3) removing alkali metal ion from a resultant extract of the step 2) by contacting the resultant extract with water; and 4) distilling the alkali metal ion-removed extract obtained from the step 3). According to the present invention, a separate formaldehyde recovery process can be omitted, the extraction efficiency of TMP can be maximized with using a relatively small amount of extraction solvent, the separation and recovery processes for extraction solvent can be simplified since a mixture of solvents is not used for TMP extraction, and the yield of TMP can be maximized while the amount of generated waste water can be minimized, thereby producing TMP economically with good efficiency.

The invention provides a method for preparing liquid alkane fuel by upgrading bio-oil in an aqueous phase catalytic mode. The method comprises the following steps of: 1) pretreating the bio-oil to obtain a water-soluble component and a water-insoluble component; 2) performing a pressurized acid hydrolysis process on a furan compound of the water-insoluble component to prepare the furan compound; 3) performing a reforming and hydrogen production reaction on the water-soluble component; 4) mixing the furan compound with a liquid-phase product separated from the step 3) to perform an aldol condensation reaction to increase carbon chains; and 5) performing a hydrogenation and dehydration reaction on an aldol condensation product to obtain liquid linear alkane. The method has the advantages that: an upgrading process, which is performed in a double-phase system, can effectively contribute to the desorption of an intermediate product from the surface of a catalyst and the mass transfer of an upgraded product, and can reduce the risk of carbon deposition on the surface of the catalyst; the quality of oil obtained by the method is high; the energy density and the energy grade of the bio-oil are improved greatly; and the liquid alkane fuel can be obtained from all kinds of bio-oil so as to partially substitute for the conventional widely-used fossil gasoline and diesel oil fuel.

The invention discloses a method of preparing long chain alkane for a jet fuel by virtue of a sugar platform compound. The method comprises the following steps: carrying out aldol condensation on the sugar platform compound in an aqueous solution under catalysis of alkali to generate a long chain oxygenated compound with ten to seventeen carbons; and then carrying out hydrogenation under the action of a metal catalyst, and finally carrying out hydrogenation, deoxidation, isomerization, cracking and cyclization under the action of the metal catalyst to generate a long chain n-alkane/isoparaffin with eight to fifteen carbons. According to the method disclosed by the invention, other organic solvents are prevented from being used, and in the condensation process, condensation products are separated from one another, a solid condensation product is directly separated from the aqueous solution, and the energy consumption is lowered; a solid product is dissolved by an alcohol solvent, the subsequent hydrogenation and deoxidation processes are carried out on the solid product, and the alcohol solvent can be provided by sugar/sugar alcohol hydrogenolysis; meanwhile, hydrogen needed by the technological process can be directly provided by the reforming process of a sugar alcohol solution, and the C component and the H component in a biological jet fuel and the solvent used in the process can be from biomass materials.

The invention relates to an ionic liquid precursor and a mesoporous material for supporting the ionic liquid precursor, synthesis and application. A preparation method comprises the following steps of: 1) synthesizing the ionic liquid precursor; 2) synthesizing the mesoporous material for supporting the ionic liquid precursor; and 3) acidizing or alkalifying the synthesized mesoporous material for supporting the ionic liquid precursor according to the requirements so as to obtain a target product. The loading capacity of the mesoporous material for supporting the ionic liquid precursor is relatively adjusted, and a mesoporous material for supporting functionalized ionic liquid can be obtained by further acidizing or alkalifying the material according to the requirements. The amount, strength of acid and alkali, properties, variety and the like of ionic liquid supported on the material are adjustable, so that the material can meet the demand of application such as various acid and alkaline catalytic reactions, chemical adsorption and separation and the like. By the material, the using amount of the ionic liquid is greatly reduced, the better catalytic effect is achieved when the material is applied to aldol condensation reactions, and the recycling of a catalyst can be realized. The kind of material is expected to be used for catalyzing more chemical reactions, and may be applied in the fields of adsorption, separation, ionic conductance and the like.

The invention relates to an aldol condensation reaction solid base catalyst and application. A composite oxide is used as a carrier which carries at least one alkali metal oxide in the catalyst, the composite oxide is a titanium oxide-aluminum oxide composite oxide or a zirconium oxide-aluminum oxide composite oxide, the mass percentage of Ti or Zr in the composite oxide is 0.1 to 30 percent, thealkali metal oxide is calcium oxide or magnesium oxide, and the mass percentage of the alkali metal in the catalyst is 0.1 to 40 percent; a fixed bed reactor is adopted, aliphatic aldehyde is contacted with the catalyst under a liquid phase condition at the temperature of between 60 and 260 DEG C to generate unsaturated aldehyde by reaction, and the catalyst is solid, so alkali aqueous solution is avoided, treatment and discharge of organic waste water are reduced, and the catalyst has excellent catalytic performance for the aldol condensation reaction; and particularly, the catalyst has goodstability, the reaction temperature is low compared with gaseous phase reaction, and the reaction result is superior to the reaction result under the gaseous phase reaction condition.

The invention provides a preparation method of neopentyl glycol, and belongs to the technical field of the preparation of alcohols. The preparation method includes the following steps: (1) regulating the pH value of a hydroxypivalaldehyde solution to 7.5-10; (2) obtaining a neopentyl glycol crude product by catalytic hydrogenation of hydroxypivalaldehyde treated by the step (1) under the effect of a hydrogenation catalyst at the temperature of 110-140 DEG C and with the pressure of 2.0-5.0 Mpa; and (3) purifying the neopentyl glycol crude product obtained in the step (2). The content of esters and other side products in the neopentyl glycol crude product prepared by the preparation method of the neopentylene glycol is extremely low, and the yield and purity of the neopentyl glycol are improved. In addition, a hydroxypivalaldehyde raw material system can be directly used for catalytic hydrogenation without any treatment, processes of aldol condensation and catalytic hydrogenation for preparation of the neopentyl glycol can be reduced, and the production efficiency can be improved.

The invention discloses a method for preparing 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate, which relates to the technical field of organic synthesis. In the invention, isobutylaldehyde is used as a raw material, aldol condensation and Cannizzaro reactions are completed by a one-step reaction process in the presence of a catalyst, and the process adopts sodium alcoholate as the catalyst; and the isobutylaldehyde is used to form alcohol ester-12 in the presence of the sodium alcoholate catalyst, so the complex and high-energy consumption drawbacks of a two-step reaction process using an inorganic alkali as a catalyst are overcome, the drawbacks of toxic catalyst and high quality requirement on the isobutylaldehyde raw material of a one-step reaction process using Ba(OH)2 as a catalyst are overcome, and simple process, high single-pass yield, small catalyst dosage, low energy consumption, safety and environmental protection are realized.

The invention belongs to the field of fine organic synthesis. The invention selects the mixture of NaCO3, Ba(OH)2, triethylamine and NaCO3, or the mixture of triethylamine and Ba(OH)2 as a catalyst, and makes use of butyraldehyde and formaldehyde to prepare 2, 2-hydroxymethyl butyric acid under the oxidation of hydrogen peroxide or oxygen through aldol condensation reaction. The invention prepares the 2, 2-hydroxymethyl butyric acid in the alkaline condition, thus the side reaction is less, the yield of the 2, 2-hydroxymethyl butyric acid is higher, and the industrialization of the invention is easy to realize.

A method for inhibiting and dissolving the deposits formed on caustic or alkaline scrubbers used in scrubbing acidic gases such as carbon dioxide, hydrogen sulfide, which are formed during the pyrolytic cracking of naphtha, ethane, and propane. The cracking operations produce certain oxygenated compounds such as vinyl acetate or acetaldehyde, which undergo polymerization under alkaline condition. The vinyl acetate on hydrolysis releases acetaldehyde under alkaline conditions. Amino acids such as 6 amino caproic acid and lactams such as epsilon caprolactam not only prevent but also dissolve the polymers formed by aldol condensation.

The invention provides a coumarin dyestuff linked by naphthene ketones, method for synthesis and use, wherein the method employs the conventional hydroxyaldehyde condensation reaction and consists of, charging naphthene ketone, corresponding aldehydes with A1 groups into reactor, obtaining semi-naphthene ketone dyestuff with A1 groups, subjecting corresponding third position methyl substituted or fourth position methyl substituted coumarin having A2 group and selenious acid in another catalyst case to obtain coumarin aldehyde having A2 group, subjecting the A1 group semi-naphthene ketone dyestuff and A2 group coumarin aldehydes to reaction at the presence of mixed solvent of dimethylbenzene and alcohol, thus obtaining coumarin type dyestuffs coupled by naphthene ketones.

The invention relates to a catalyst for aldol condensation reaction and a preparation method of the catalyst. The catalyst is prepared by an immersion method, the active ingredient main catalyst is alkali metals or alkaline earth metals, and the cocatalyst is rare earth metals; and the catalyst is obtained by loading one or more of alkali metals or alkaline earth metals on a carrier, simultaneously loading one or more of rare earth metals and calcining at a certain temperature. The catalyst has the characteristics of simple preparation method, low price, high catalytic activity and long life.

The invention discloses a water resistant catalyst for aldol condensation. The water resistant catalyst comprises a main active ingredient, an active agent and a carrier, wherein the main active ingredient is one or more selected from oxides or salts of Cs; the active agent is one or more selected from oxides or salts of Sb, Nb, Ag, Al and Zr; the carrier comprises SiO2 and a carrier aid; the carrier aid is one or more selected from Al2O3, ZrO2, diatomite and kaolin; the SiO2 is hydrophobic nano SiO2; or (2) the catalyst is subjected to water-resistant treatment. The water resistant catalyst is used for aldol condensation, has the characteristics of high activity, high selectivity and long service life, is especially used for synthesizing methyl methacrylate through formaldehyde and methyl propionate. With calculation of methyl propionate, the selectivity of methyl methacrylate is 94 percent, and the single service life of the catalyst is over 400 hours. The catalyst is simple in preparation method and is suitable for industrial application.

Disclosed is an asymmetric total-synthesis method for chiral huperzine a. The method takes 1,4-dihydro-spiro (4,5) -8 -decanone as starting material to get benzoate through hydroxymethylation and the treatment of benzoyl chloride and K2CO3; the benzoate is reacted with hydrogen sulfate O-methyl iso urea to get quinazoline; after the ketal is eliminated, Mander reagent is used for methyl esterification reaction so as to obtain beta-keto ester. Chiral ammonia, such as cinchona alkaloid, is used to promote the tandem asymmetric Michael addition/aldol condensation reaction of beta-keto esters and methyl acrolein. The compound carboxylate of diastereoisomer is reacted with MsCl, triethylamine and DMAP to get transformed. Through TMSI and MeOH processing, the protective group is removed so as to obtain optically pure-chiral huperzine a.

The present invention relates to the co-production of unsaturated aldehydes via a crossed-aldol condensation reaction catalyzed by recyclable water-soluble phase-transfer catalysts or the hydroxides thereof. The aldehydes are then hydrogenated to the desired alcohol products or saturated aldehyde feed stocks. Specifically, methods in which 2,4-diethyloctanol is co-produced with 2-ethylhexanol in batch and continuous processes are described. Recovery of the phase-transfer catalyst through water washing followed by "salting out" from the washings is also demonstrated.