55results about "Preparation by isomerisation" patented technology

The invention belongs to the technical field of organic synthesis, and particularly discloses a method for synthesizing carveol hydrate by using 2, 3-epoxy pinane, which comprises the following steps: by using 2, 3-epoxy pinane as a raw material, adding deionized water in a solvent in the presence of organic phosphoric acid as a catalyst and a micro-channel reactor as reaction equipment, carrying out ring-opening rearrangement reaction on the 2, 3-epoxy pinane to obtain carveol hydrate. Under the combined action of the catalyst and the microchannel reactor, high-yield and high-purity carveol hydrate is obtained; the method is mild in reaction condition, simple and convenient to operate, capable of effectively avoiding violent heat release of epoxy ring opening and generated by-products, high in reaction efficiency and good in industrial application prospect, the product yield can reach 98%, and the content can reach 99%.

The invention provides a method for preparing allyl alcohol through epoxypropane isomerization, and relates to the technical field of chemical synthesis. According to the method, propylene oxide is subjected to an isomerization reaction in the presence of a polymerization inhibitor to prepare allyl alcohol; wherein the polymerization inhibitor is a phenol polymerization inhibitor and / or a quinone polymerization inhibitor. The technical scheme of the invention can effectively reduce the deactivation rate of the catalyst and prolong the service life of the catalyst. The method for preparing allyl alcohol through epoxypropane isomerization is high in production efficiency and low in production cost, and has important industrial application value.

The present invention relates to a method for the preparation of 3-methyl-3-butene-1-ol (isoprenol), comprising the steps of preparing isobutylene (also: isobutene, 2-methylpropene) by contacting 3-methylbutan-1-ol (isoamyl alcohol) to a catalyst comprising at least one catalytically active metal and reacting at least one formaldehyde source and the isobutylene obtained in step a-i) to obtain isoprenol. Furthermore, the present invention refers to processes for the preparation of 3-methyl-2-butene-1-ol (prenol), of 3-methyl-3-butenal (isoprenal), of 3-methyl-2-butenal (prenal), and of 3,7-dimethy l-octa-2, 6-dienal (citral) and further downstream products comprising the use of isoprenol of the present invention and the resulting products and product streams.

A process for the manufacture of a chemical of interest comprises subjecting a feedstock comprising a renewably-sourced ethanol to dehydration to produce a renewably-sourced ethylene stream, which is subjected to an olefin-interconversion to obtain one or more renewably-sourced C3-4-olefins, selected from propylene, n-butenes and isobutene. Further, the renewably-sourced C3-4-olefin is subjected to a chemical conversion or sequence of chemical conversions to obtain the chemical of interest, the chemical conversion or sequence of chemical conversions producing one or more crude product streams and, optionally, one or more crude intermediate product streams. Subsequently, at least one of the crude product stream(s) and optional intermediate crude product stream(s) is subjected to purification producing one or more purified product streams, one or more waste streams and, optionally, one or more purified intermediate product streams. Then, at least one of the waste streams is incinerated to produce thermal energy. The process provides a reaction scheme that provides renewably-sourced ethylene-derived chemical of interest, while minimizing both fossil carbon dioxide emissions and consumption of renewably-sourced feedstock.

The invention discloses a boron-containing metal doped catalyst and a preparation method and application thereof.The catalyst comprises active metal components existing in the form of phosphate and a boron-containing compound, the active metal components comprise a first active metal component Li and further comprise at least one of second active metal components Be, Na, K, Mg, Zn, Fe and Ba, and the boron-containing compound is a boron-containing compound. The second active metal component at least accounts for 5.3 wt% of the catalyst, and the boron-containing compound accounts for 1.3 wt% of the catalyst. The catalyst provided by the invention improves the conversion rate and selectivity in catalyzing the isomerization reaction of epoxypropane, and especially improves the stability.

The present invention relates to the field of organic synthesis and more specifically it concerns a process for the rearrangement of epoxides into allylic alcohols in a presence of zinc catalyst and two amino phenol.

The invention belongs to the technical field of synthesis of medicines and spices, and particularly relates to a synthesis method of trans-2-octenal. The synthesis method comprises the following steps: carrying out isomerization reaction on 1-octylene-3-alcohol under the catalytic action of 3, 4-dinitrobenzoic acid to obtain a trans-2-octylene-1-alcohol intermediate; the preparation method comprises the following steps: preparing trans-2-octenal from trans-2-octylene-1-alcohol under the oxidation action of m-chloroiodobenzene, 4-hydroxy-TEMPO (4-hydroxy-2, 2, 6, 6-tetramethylpiperidine nitroxide free radical) and peracetic acid, and further preparing the trans-2-octenal from the trans-2-octylene-1-alcohol. The preparation method is mild in reaction condition, simple to operate and free of expensive reagents or catalysts.

The present invention relates to a method for preparing 3-methyl-2-butenal (prenal), 3-methyl-2-buten-1-ol (prenol), diprenyl acetate of prenal, and 3,7-dimethyl-octa-2,6-dienal (citral), wherein the aldehyde content in one or more reaction flows is maintained below a threshold. Furthermore, the present invention relates to available product flows of prenal, prenol, diprenyl acetate of prenal, and citral.

Organically bound nitrogen is removed from an ethylenically unsaturated alcohol stream by contacting the alcohol stream with a weakly acidic solid adsorbent. Trace amounts of organically bound nitrogen tend to poison the oxidation catalyst in subsequent oxidation processes using the ethylenically unsaturated alcohol stream.

The application provides a method for synthesizing 3-methyl-2-buten-1-ol, and belongs to the technical field of isopentenol synthesis. The method comprises the following steps: introducing 3-methyl-3-buten-1-ol and an atmosphere containing hydrogen into a fixed bed reactor, and performing a hydrogenation isomerization reaction under the action of a Pd / Al2O3 catalyst to generate 3-methyl-2-buten-1-ol; wherein the content of formaldehyde in the 3-methyl-3-buten-1-ol is 0.03-0.15%. The application adopts a fixed bed reactor to perform continuous production, adopts a Pd / Al2O3 catalyst with low palladium content as the catalyst, the preparation method is simple, the price is relatively low, and the content of formaldehyde in the 3-methyl-3-buten-1-ol is controlled to inhibit a side reaction, so that the reaction conversion rate and the product selectivity are high.

The present invention relates to a process for the preparation of self-supported chiral catalyst polymers via non-radical polymerization and the catalyst polymers thus obtained. A novel at least heterogeneous chiral catalyst readily obtainable via self-supported non-radical polymerization using a homogeneous chiral catalyst and optionally a homogeneous linker is disclosed. These heterogeneous chiral materials can be used as catalysts for different chemical conversions.

The invention relates to a process for the preparation of an unsaturated alcohol of formula (I) comprising subjecting an unsaturated aldehyde of formula (II) to hydrogenation in the presence of a catalyst and a tertiary amine; characterized in that the hydrogenation is carried out in a reactor cascade. Hydrogenation in a cascade of reactors, in particular a cascade of stirred tank reactors, a cascade of bubble column reactors, or a cascade of jet loop reactors reduces the amount of by-products formed and increases the yield and selectivity of the products.

A method is disclosed for isomerizing a feed containing an olefinically unsaturated alcohol by shifting a double bond to obtain an isomerized olefinically unsaturated alcohol. The method includes providing a cascade of n reactors, where n is an integer of at least 2. The method further includes merging an i-th supplementary stream with an i-th recycle stream to obtain an i-th reactor inlet stream; feeding the i-th reactor inlet stream into the i-th reactor and isomerizing the i-th reactor inlet stream on a heterogeneous isomerization catalyst to produce an i-th effluent stream; and splitting the i-th effluent stream into the i-th recycle stream and an i-th forward stream. In this method, i ranges from 1 to n; where for i=1, the feed constitutes the first supplementary stream, and for i=2 to n, the (i-1)-th forward stream constitutes the (i)-th supplementary stream; and the n-th forward stream is the product stream. This method allows for the isomerization of olefinically unsaturated alcohols with high conversion and improved selectivity.

The invention discloses a racemic catalyst preparation device, comprising a fixed outer frame and a reactor, the reactor can be flipped and installed on the fixed outer frame, the reactor comprises a sealing cover and a reaction box, the inner side of the sealing cover is covered with a heating plate, the interior of the reaction box is spherical and bowl-shaped and recessed, the interior of the reaction box is provided with a leak-proof plate, a heating arc plate and a screen plate from the outside to the inside, the leak-proof plate is connected to the inner bottom surface of the reaction box by a plurality of springs, a through cylinder is installed at the bottom center of the screen plate, a driving rod is vertically provided in the reactor, the driving rod is driven to move vertically and rotate axially, a stirring assembly is axially rotatably provided on the outside of the driving rod, the driving rod can respectively drive the stirring assembly and the screen plate to rotate, a liquid outlet pipe is provided at the bottom end of the driving rod, a plurality of drainage ports connected to the liquid outlet pipe are provided on the outer peripheral surface of the bottom end of the driving rod, the bottom center of the leak-proof plate is penetrated by the liquid outlet pipe, and a through outlet is provided at the bottom center of the reaction box.

The present invention provides a samarium diiodide-mediated cyclopropane ring-opening and deuteration method and application, comprising the following steps: preparing a samarium diiodide solution; sequentially adding a nitrogen-containing alkaline compound and a deuterium source to the solution; subsequently adding an ester substrate, stirring the solution for reaction, and bubbling air to oxidize the excess samarium; sequentially adding dichloromethane and hydrochloric acid, diluting, separating the layers, and extracting the aqueous layer with an extractant; combining the remaining organic layers, drying, filtering, and then distilling under reduced pressure to purify the residue. This method utilizes inexpensive heavy water as a deuterium donor, combining SmI2-promoted cyclopropane ring-opening with the reduction of a carboxylic acid derivative to achieve deuteration reactions at multiple positions. Furthermore, the SmI2 / D2O system exhibits significantly broader substrate compatibility. By adjusting the reagent dosage to form different strategies for cyclopropane ring-opening and reductive deuteration, deuterium can be efficiently introduced into a variety of substrates, including ketones, esters, nitriles, acyl chlorides, acyl fluorides, and oximes.

This invention provides a method for isomerizing 3-butenol compounds in a hydrogen-medium environment to prepare 2-butenol compounds, comprising the following steps: In a hydrogen atmosphere, a mixture of an inorganic base and a 3-butenol compound is passed through a catalyst bed to undergo an isomerization reaction, yielding the 2-butenol compound; the amount of inorganic base added is 0.01–1.5% of the mass of the 3-butenol compound; the catalyst is porous silica supported on palladium, cerium, and selenium. This invention, by adding an additional base to the 3-butenol feedstock, effectively prevents the unsaturated alcohol from converting to a saturated alcohol during the hydrogen-containing isomerization process. Simultaneously, the addition of the electron promoter selenium to the catalyst in this application inhibits the adsorption capacity of the palladium catalyst for hydrogen, thereby reducing the hydrogenation activity of the palladium catalyst while maintaining the stability of the palladium compound cation. Furthermore, the structure promoter cerium improves the diffusivity of palladium, increases the active centers and coordination of palladium, and structurally improves the performance of the palladium catalyst.

The present invention relates to a process for the preparation of unsaturated alcohols of the formula (I), which comprises subjecting unsaturated aldehydes of the formula (II) to a hydrogenation in the presence of a catalyst and a tertiary amine; characterized in that the hydrogenation takes place in a reactor cascade. Conducting the hydrogenation in a reactor cascade, in particular a cascade of stirred vessel reactors, a cascade of bubble column reactors, or a cascade of jet loop reactors, reduces the amount of formed side products and enhances yield and selectivity of the products.

The application discloses a method for preparing borneol by continuously dehydrogenating and hydrogenating isoborneol, which comprises the following steps: dissolving isoborneol in an organic solvent, mixing the isoborneol with hydrogen, and carrying out dehydrogenation and hydrogenation reaction in a catalytic reactor by a two-stage temperature method, so as to realize the preparation of borneol products; and the reactor is loaded with a catalyst which takes one or more of Ru, Rh, Pd, Pt, Cu, Co, Ni and Fe as an active component and takes alumina, titania or silicon oxide as a carrier. The method can improve the conversion rate of isoborneol and the yield of borneol, and the content of borneol in the obtained product meets the requirements of pharmacopoeia.

A process for isomerizing a first olefinically unsaturated alcohol by shifting a double bond to obtain a second olefinically unsaturated alcohol, the process comprising contacting a stream of the first olefinically unsaturated alcohol with at least one heterogeneous isomerization catalyst, characterized in that the stream of the first olefinically unsaturated alcohol contacted with the heterogeneous isomerization catalyst comprises less than 25 ppmw of organically bound nitrogen relative to the weight of the first olefinically unsaturated alcohol. The process allows isomerizing olefinically unsaturated alcohols with high selectivity.

In accordance with the purpose(s) of the present disclosure, as embodied and broadly described herein is versatile polyene cyclization strategy that exploits conjugated b-ionyl derivatives. Photomediated disruption of the extended p-system within these chromophores unveils a contra-thermodynamic polyene that engages in a Heck-type cyclization to afford [4.4.1]-propellanes. The connectivity of overbred polycycles generated from this process is controlled by the position of the requisite C–Halide bond. Thus, compared to conventional biomimetic polyene cyclization, this approach allows for complete control of regiochemistry and facilitates incorporation of both electron-rich and electron-deficient (hetero)aryl groups. This strategy was successfully applied to the total synthesis of abietanes such as, for example, taxodione and salviasperanol, two isomeric abietane-type diterpenes that previously could not be prepared along the same synthetic pathway.

The invention relates to a process for the preparation of 3-methyl-2-butenal (isopentenal), for the preparation of 3-methyl-2-buten-1-ol (isopentenol), for the preparation of diisopentenyl acetic acid esters for the preparation of isopentenal, and for the preparation of 3, 7-dimethyl-oct-2, 6-dienal (citral), in particular to a process for the preparation of 3, 7-dimethyl-oct-2, 6-dienal. Wherein the aldehyde content in the one or more reactant streams is maintained below a threshold. Furthermore, the present invention relates to product streams of isopentenal, isopentenol, diisopentenyl acetate of isopentenal, and citral, which can be obtained.

The present invention relates to the field of organic synthesis, and more specifically to a method for the rearrangement of epoxides to allylic alcohols in the presence of a zinc catalyst and two aminophenols.

The invention provides a method for preparing n-hexanol through a continuous reaction, which comprises the following steps: (1) carrying out an isomerization reaction on a raw material butyl ethylene oxide under the action of an isomerization catalyst to obtain an isomerization reaction solution; (2) carrying out hydrogenation reaction on the isomerization reaction liquid under the action of a hydrogenation catalyst to obtain hydrogenation reaction liquid; and (3) carrying out post-treatment on the hydrogenation reaction liquid to obtain the n-hexanol, wherein the isomerization catalyst is a supported catalyst and comprises a carrier, an active metal component and a metal additive, the carrier is one of aluminum oxide, silicon oxide, silicon nitride, silicon carbide, SBA-15 and a molecular sieve, the active metal component is one or more of chromium, niobium, zirconium, molybdenum and tungsten, and the metal additive is one or more of potassium, calcium, zinc, copper, gallium and indium. According to the invention, the hydrogenation catalyst is directly added into the isomerization reaction liquid obtained by the isomerization reaction to carry out the hydrogenation reaction, and the obtained hydrogenation reaction liquid is separated and purified to obtain the high-purity n-hexanol product. In the isomerization reaction, the active components and auxiliary components in the isomerization catalyst cooperate to catalyze and inhibit side reactions such as dehydration and polymerization in the isomerization reaction, and high target product selectivity and high stability are obtained.

The present invention relates to a method, comprising the isomerization of neral of formula (II) to geranial of formula (I), or the isomerization of geranial to neral, characterized in that (a) the isomerization is accomplished by irradiation with light. The method according to the present invention makes it possible to convert an undesired isomer, which is an unavoidable by-product generated during the production of neral and / or geranial, into a desired isomer highly efficiently, thus greatly improving the economic performance of the method for producing the desired isomer (in high yield by avoiding cost intensive distillation and with avoiding possible side products).

This invention discloses a method for resolving racemic mixtures based on dynamic kinetics, belonging to the field of catalysis technology. The method includes the following steps: taking a proton-selective permeable membrane and pretreating it; using the pretreated proton-selective permeable membrane to separate the aqueous phase and organic phase for reaction, thereby resolving the racemic mixture; wherein the aqueous phase is an acid solution, and the organic phase contains at least the racemic mixture, an acyl donor, an enzyme, and an organic solvent, and the racemic mixture is a racemic mixture of a chiral secondary alcohol or its derivative. This invention utilizes a proton-selective permeable membrane as a racemic catalyst applied to the dynamic kinetic resolution process, solving the problem of incompatibility between racemic catalysts and enzyme catalysts in conventional dynamic kinetic resolution techniques. This method has advantages such as a simple reaction system, easy process control, environmental friendliness, simple post-processing, and low cost.

The invention provides an olefin hydroisomerization heterogeneous cobalt-nitrogen-carbon catalyst, a preparation method and application. The invention belongs to the technical field of fine chemical engineering. According to the technical scheme, a cobalt and zinc bimetal organic framework material is adopted as a precursor, and the cobalt-nitrogen-carbon catalyst is prepared through roasting in an inert atmosphere. The catalyst is simple in preparation process, low in cost, good in stability and easy to separate. The terminal olefin can be efficiently converted into the internal olefin only by using a small amount of catalyst, the required time is short, the conversion rate is high, the reaction selectivity is good, and the E / Z ratio is high.

The present invention relates to processes for preparing 3-methyl-2-butenal (prenal), for preparing 3-methyl-2-buten-1-ol (prenol), for preparing diprenyl acetate of prenal as well as for preparing 3,7-dimethyl-octa-2,6-dienal (citral), wherein the aldehyde contents in one or more reactant streams are maintained to be below thresholds. Furthermore, the present invention relates to obtainable product streams of prenal, prenol, diprenyl acetate of prenal as well as citral.

The application belongs to the technical field of medicine and spice synthesis, and particularly relates to a synthesis method of trans-2-octenal. The synthesis method comprises the following steps: 1-octene-3-ol is subjected to isomerization reaction under the catalysis of 3,4-dinitrobenzoic acid to obtain a trans-2-octene-1-ol intermediate; and the trans-2-octene-1-ol is subjected to oxidation by interchloroiodobenzene, 4-hydroxy-TEMPO (4-hydroxy-2,2,6,6-tetramethylpiperidinooxy) and peroxoacetic acid to obtain the trans-2-octenal. The preparation method has mild reaction conditions, simple operation and does not need to use expensive reagents or catalysts.

The invention belongs to the technical field of pharmaceutical chemicals, and particularly discloses a bicyclo [2.1. 1] hexane derivative as well as a preparation method and application thereof. The bicyclo [2.1. 1] hexane derivative is a compound as shown in a formula (I) or a formula (II), a pharmaceutically acceptable salt, a stereoisomer or an isotope label of the bicyclo [2.1. 1] hexane derivative, wherein R1 is optionally selected from C1-C6 alkyl groups, bromomethyl alkyl, benzyl alkyl, ester groups, acylamino and acyl groups; r2 is optionally selected from hydrogen, C1-C6 alkyl, benzyl alkyl, aryl, heteroaryl, alkenyl, halogen and silicon; r3 is optionally selected from hydrogen, C1-C6 alkyl, bromomethyl alkyl, benzyl alkyl, an ester group, an acylamino group, an acyl group, an amido group, a sulfenamide group, halogen and a carboxyl group; and R4 is optionally selected from C1-C6 alkyl, benzyl alkyl, aryl, heteroaryl and alkenyl. And the formula (II) can be obtained by carrying out half-pinacol intramolecular rearrangement on the formula (I). Tests prove that the compounds in the formula (I) and the formula (II) can be used for treating osteoarthritis diseases.