- METHOD FOR PRODUCING CARBAMATE AND METHOD FOR PRODUCING ISOCYANATE
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The present invention provides a method for producing a carbamate that includes a step (1) and a step (2) described below: (1) a step of producing a compound (A) having a urea linkage, using an organic primary amine having at least one primary amino group per molecule and at least one compound selected from among carbon dioxide and carbonic acid derivatives, at a temperature lower than the thermal dissociation temperature of the urea linkage; and(2) a step of reacting the compound (A) with a carbonate ester to produce a carbamate.
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- Process of preparing isocyanate compounds comprising non-chlorination derivatives and Composition thereof
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The present invention relates to a process for producing xylylene diisocyanate. The present invention relates to a process for preparing isocyanates comprising the obtained non-chlorinated derivatives. In particular, the present invention relates to an isocyanate composition comprising an unchlorinated derivative obtained by the reduction reaction and a polymerizable composition including the same.
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Paragraph 0149-0166
(2021/10/05)
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- Method for preparing high-purity m-xylylene diisocyanate from non-phosgene
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The invention relates to the technical field of isocyanate preparation, in particular to a method for preparing high-purity m-xylylene diisocyanate from non-phosgene. The method for preparing the high-purity m-xylylene diisocyanate from the non-phosgene comprises the following steps: subjecting m-xylylenediamine and dimethyl carbonate to reacting under the action of a catalyst A to obtain methyl m-xylylene dicarbamate; and carrying out a decomposition reaction on methyl m-xylylene dicarbamate under the action of a catalyst B, emptying methanol through nitrogen replacement in the reaction process, and carrying out reduced-pressure distillation after the reaction is finished so as to obtain m-xylylene diisocyanate, wherein the catalyst A is a supported catalyst taking Lewis acid as an activecomponent and nano-SiO2 or nano-TiO2 as a carrier, and the catalyst B is an ultrafine composite oxide. The preparation method of the invention is good in product selectivity, high in yield, high in purity and free of catalyst residues, product quality is improved, and the requirements of high-end fields are met.
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Paragraph 0062-0076; 0080-0091
(2021/03/31)
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- DIISOCYANATE COMPOSITION, PREPARATION METHOD THEREOF AND OPTICAL MATERIAL USING SAME
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The diisocyanate composition according to an embodiment of the present invention comprises, in the composition, a benzyl isocyanate having a methyl group in an amount of 5 ppm to 200 ppm, an aromatic compound having a halogen group in an amount of 5 ppm to 1,000 ppm, a benzyl isocyanate having an ethyl group in an amount of 1 ppm to 1,000 ppm, or a combination thereof. It is possible to improve the optical characteristics by preventing the occurrence of yellowing, striae, and cloudiness and to enhance the mechanical properties such as impact resistance at the same time. Thus, it can be advantageously used to prepare an optical material of high quality.
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Paragraph 0212-0215; 0243-0246; 0274-0277; 0280-0282
(2021/06/11)
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- METHOD OF PREPARING DIISOCYANATE COMPOSITION AND OPTICAL LENS
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In the embodiments, an aqueous hydrochloric acid solution instead of hydrogen chloride gas and solid triphosgene instead of phosgene gas may be used in the process of preparing a diisocyanate from a diamine through a diamine hydrochloride. In addition, the embodiments provide processes for preparing a diisocyanate composition and an optical lens of higher quality, in which the reaction temperature of a diamine hydrochloride composition and triphosgene is controlled to a specific range, or a crude diisocyanate composition obtained from the reaction of a diamine hydrochloride composition and triphosgene is distilled at a specific temperature range, or the molar ratio of a diamine hydrochloride and triphosgene is adjusted to a specific range.
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Paragraph 0175-0179; 0195-0199; 0218-0221
(2021/06/11)
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- Construction of unsymmetrical bis-urea macrocyclic host for neutral molecule and chloride-ion binding
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Construction of synthetic macrocyclic host that can bind with neutral molecules and anions has potential applications in supramolecular chemistry. Herein, we have designed and synthesized blue light emitting an unsymmetrical neutral bis-urea macrocyclic host. This macrocycle can bind with neutral DMF molecule (1:1) as well as Cl? ion (1:1) through noncovalent interactions. X-Ray crystal structure, 1H NMR titrations with Job's Plot, HRMS with isotropic distribution pattern, FT-IR, and density functional theory analysis revealed the binding of bis-urea macrocyclic host with the guest molecule.
- Bhuyan, Deepak,Guha, Samit,Mukherjee, Ayan,Paul, Biprajit
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supporting information
(2021/06/27)
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- METHOD OF PREPARING DIISOCYANATE COMPOSITION
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In the embodiments, an aqueous hydrochloric acid solution instead of hydrogen chloride gas and solid triphosgene instead of phosgene gas may be used in the process of preparing a diisocyanate from a diamine through a diamine hydrochloride. In addition, the embodiments provide processes for preparing a diisocyanate composition and an optical lens, which are excellent in yield and quality with mitigated environmental problems by controlling the size of the diamine hydrochloride composition, the b* value according to the CIE color coordinate of the diamine hydrochloride composition, or the content of water in the diamine hydrochloride composition within a specific range.
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Paragraph 0219-0226; 0243-0245; 0252-0254; 0277-0279
(2021/06/11)
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- METHOD OF PREPARING DIISOCYANATE COMPOSITION AND OPTICAL LENS
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In the embodiments, an aqueous hydrochloric acid solution and an organic solvent instead of hydrogen chloride gas and solid triphosgene instead of phosgene gas may be used in the process of preparing a diisocyanate from a diamine through a diamine hydrochloride. In addition, the embodiments provide processes for preparing a diisocyanate composition and an optical lens, which are excellent in yield and quality with mitigated environmental problems by controlling the total content of metals, cations, or anions in a diamine hydrochloride composition.
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Paragraph 0189-0200; 0222-0230; 0268-0276
(2021/06/11)
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- Method for preparing low-chlorinated impurity content isocyanate based on salt formation light gasification (by machine translation)
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The invention provides a method for preparing low-chlorinated impurity content isocyanate based on a salt-formation light gasification method. The proportion of the salt particle size distribution obtained by the salt formation reaction in the average particle size ±30% range is 70% or more, the average residence time without stirring is less than 60 min, and the product obtained by the method has lower chlorinated impurity content. (by machine translation)
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Paragraph 0063-0064; 0075-0076; 0077-0078; 0088-0089
(2020/10/14)
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- Process of preparing isocyanate compounds comprising non-chlorination derivatives and Composition thereof
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The present invention relates to a method for preparing isocyanates containing a non-chlorinated derivative obtained by converting a chlorinated derivative generated in a preparation process of xylylene diisocyanate into a non-chlorinated derivative by a reduction reaction. In particular, the present invention relates to an isocyanate composition comprising the non-chlorinated derivative obtained by the reduction reaction and a polymerizable composition comprising the same. The isocyanate composition is excellent in economic feasibility and easy to reduce chlorinated derivatives.COPYRIGHT KIPO 2021
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Paragraph 0149-0151
(2020/12/15)
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- ISOCYANATE PRODUCTION METHOD
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An isocyanate production method according to the present invention is a method in which an isocyanate is produced by subjecting a carbamate to thermal decomposition, and includes: a step of preparing a mixture liquid containing the carbamate, an inactive solvent and a polyisocyanate compound; a step of conducting a thermal decomposition reaction of the carbamate by continuously introducing the mixture liquid into a thermal decomposition reactor; a step of collecting a low-boiling decomposition product by continuously extracting the low-boiling decomposition product in a gaseous state from the reactor, the low-boiling decomposition product having a boiling point lower than the polyisocyanate compound; and a step of collecting a high-boiling component by continuously extracting, from the reactor, a liquid phase component which is not collected in a gaseous state at the step of collecting the low-boiling decomposition product.
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Paragraph 0447-0450; 0459; 0478
(2020/05/02)
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- Preparation method for isophthalylidene diisocyanate
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The invention discloses a preparation method for isophthalylidene diisocyanate. The preparation method comprises the following step of preparing isophthalylidene diisocyanate through a cold photochemical reaction and a thermal photochemical reaction by taking m-xylylenediamine and phosgene as raw materials and a mixed inert organic solvent as a solvent. By adopting the cold and thermal photochemical-mixed solvent method, the selectivity of the reaction under the action of a pyridine catalyst can be improved. In an obtained isophthalylidene diisocyanate product, the content of 3-chloro methyl-benzyl isocyanate is controlled below 0.2%, the content of isophthalylidene diisocyanate is controlled to be greater than or equal to 99.5%, and the yield is greater than or equal to 96% (based on m-xylylenediamine). The preparation method has the advantages of being good in reaction selectivity, high in yield, high in product purity, low in impurity content and the like, can be used for obtainingthe isophthalylidene diisocyanate product which is high in quality and has good industrial value and application prospect.
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Paragraph 0035-0088
(2019/03/08)
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- Method used for preparing m-xylylene diisocyanate
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The invention relates to a method used for preparing m-xylylene diisocyanate. The method comprises following steps: m-xylylene diamino ethyl formate is dissolved in an organic solvent, under protective gas purging, thermal decomposition reaction is carried out so as to obtain the m-xylylene diisocyanate. The preparation technology is simple and convenient, is friendly to the environment, is low incost, and is capable of realizing amplification production; the adopted reaction solvent can be recycled; and the product yield is high.
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Paragraph 0036-0050
(2019/11/29)
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- ISOCYANATE COMPOSITION FOR OPTICAL LENSES AND PREPARATION METHOD THEREOF
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The present invention can easily manufacture an optical lens with high quality by controlling the composition of isocyanate used for manufacturing polythiourethane by manufacturing an isocyanate composition using an amine composition including: from 99% by weight to less than 100% by weight of m-xylylenediamine; more than 0 to 0.5% by weight of p-xylylenediamine; and one or more members selected from a group consisting of benzylamine, 4-methylbenzylamine and 4-cyanobenzylamine in an amount of more than 0% by weight to 0.5% by weight or less.COPYRIGHT KIPO 2019
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Paragraph 0139; 0140-0150
(2019/02/16)
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- XYLYLENE DIISOCYANATE COMPOSITION WITH IMPROVED STABILITY AND REACTIVITY, AND OPTICAL LENS USING THE SAME
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In the embodiment according to the reel [leyn [leyn] the dee small city this [thu [thu] which it knows the xylose composition having improved stability even in long-term storage 100 - 1000 ppm chlorine content adjusted wherein the reactive can be prevented from being lowered. In the embodiment according to the xylose after long-term storage for products after the reel [leyn [leyn] the dee small city this [thu [thu] which it knows composition number bath although, refractive index polymers with mote this year, an Abbe number, transparency, glass transition temperature, excellent property such as index to a polythiourethane optical material can be bath in number, spectacle lenses, camera lens or the like in fields useful. (by machine translation)
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Paragraph 0104-0106
(2019/02/26)
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- Preparation method of methylene diphenyl diisocyanate
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The invention provides a preparation method of methylene diphenyl diisocyanate. The method comprises the following steps: performing a salt forming reaction on m-xylylenediamine and hydrogen chloride gas to obtain m-xylylenediamine hydrochloride; mixing the m-xylylenediamine hydrochloride, an organic phosphorus compound and solid phosgene for reaction to obtain methylene diphenyl diisocyanate. In a process of preparing methylene diphenyl diisocyanate, according to the application, an organic phosphorus compound additive is introduced, so that the reaction of m-xylylenediamine hydrochloride is promoted, therefore, the reaction rate and the effective conversion rate are improved.
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Paragraph 0043; 0044; 0045; 0046
(2017/07/19)
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- Preparation method for benzene dimethylene diisocyanate
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The invention belongs to the field of chemical synthesis and especially relates to a preparation method for benzene dimethylene diisocyanate. The method comprises the following steps: a) performing acylating chlorination reaction on triphosgene and m-xylylenediamine in a solvent under the existence of catalyst and acid-binding agent, thereby acquiring reaction liquid, wherein the catalyst contain trimethylchlorosilane and/or hexamethyl-disilazane and the acid-binding agent contains one or more of triethylamine, pyridine and dimethyl formamide; b) heating the reaction liquid and reacting, thereby acquiring benzene dimethylene diisocyanate. According to the invention, triphosgene and m-xylylenediamine are used as initial raw materials, the benzene dimethylene diisocyanate is prepared in two steps under the existence of catalyst and acid-binding agent and the technology is simple. According to the method provided by the invention, the benzene dimethylene diisocyanate can be prepared under normal pressure, the reaction condition is easily controlled and the safety factor is high. Besides, the preparation method provided by the invention is higher in product yield.
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Paragraph 0043; 0044; 0045; 0046; 0047; 0048; 0049-0058
(2018/01/03)
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- Preparation method of isocyanate
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The invention provides a method for preparing isocyanate based on a salifying phosgenation method. A salt forming reaction in the method comprises the following two steps: firstly, performing preliminary salt forming reaction by adopting a conventional reactor; secondly, adding a moderately polar organic solvent with a certain proportion into a reactor provided with an hourglass type liquid slurry disperser to carry out salt forming curing reaction, wherein star-shaped discharge openings are arrayed in a cylinder body of the hourglass type disperser. According to the preparation method, the fact that amino groups in raw materials are converted into amine hydrochlorides with high conversion rate can be ensured through the salt forming curing reaction, and the isocyanate product can be obtained with high yield through a follow-up photochemical reaction.
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Paragraph 0105-0109
(2017/01/09)
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- METHOD FOR PRODUCING META-XYLYLENEDIISOCYANATES
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A method for producing meta-xylylenediisocyanates includes a reaction step in which monohalogenated benzenes, formaldehydes, and an amide compound represented by general formula (1) below are allowed to react in the presence of an acidic liquid to produce a bisamide compound; a dehalogenation step in which in the bisamide compound, the halogen atom derived from the monohalogenated benzenes is replaced with a hydrogen atom; and a thermal decomposition step in which the bisamide compound from which the halogen atom is eliminated is subjected to thermal decomposition. In the reaction step, the acidic liquid contains inorganic acid, the equivalent ratio of the hydrogen atom of the inorganic acid relative to the monohalogenated benzenes is more than 14, the acidic liquid has an inorganic acid concentration of more than 90 mass %, and the reaction temperature is more than 10° C. [in-line-formulae]General formula (1):[/in-line-formulae] wherein R1 represents an alkoxy group or an amino group.
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Paragraph 0205; 0206
(2016/06/13)
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- METHOD FOR PRODUCING M-XYLYLENE DIISOCYANATE
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A method for producing meta-xylylenediisocyanates includes a reaction step in which monohalogenated benzenes, formaldehydes, and an amide compound represented by general formula (1) below are allowed to react in the presence of an acidic liquid to produce a bisamide compound; a dehalogenation step in which in the bisamide compound, the halogen atom derived from the monohalogenated benzenes is replaced with a hydrogen atom; and a thermal decomposition step in which the bisamide compound from which the halogen atom is eliminated is subjected to thermal decomposition. In the reaction step, the acidic liquid contains inorganic acid, the equivalent ratio of the hydrogen atom of the inorganic acid relative to the monohalogenated benzenes is more than 14, the acidic liquid has an acid concentration of more than 90 mass%, and the reaction temperature is more than 10°C. General formula (1): (in general formula (1), R 1 represents an alkoxy group or an amino group).
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Paragraph 0265; 0266
(2016/10/08)
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- METHOD FOR PRODUCING CARBAMATE COMPOUND, CARBAMATE COMPOUND, AND METHOD FOR PRODUCING ISOCYANATE COMPOUND USING SAME
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The present invention relates to a method of producing a carbamate compound, comprising reacting a fluorine-containing carbonic diester compound represented by formula (1) and a non-aromatic diamine compound represented by formula (2) without using a catalyst, to thereby produce a carbamate compound represented by formula (3), and a method of producing an isocyanate compound represented by formula (20) from the carbamate compound without using a catalyst, wherein R represents a fluorine-containing monovalent aliphatic hydrocarbon group, and A represents a divalent aliphatic hydrocarbon group, a divalent alicyclic hydrocarbon group or a divalent aromatic-aliphatic hydrocarbon group. [Chem. 2] ????????H2N-A-NH2?????(2) [Chem. 4] ????????O=C=N-A-N=C=O?????(20)
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Paragraph 0084
(2013/03/26)
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- COSMETIC OR DERMATOLOGICAL COMPOSITION COMPRISING A POLYMER BEARING JUNCTION GROUPS, AND COSMETIC TREATMENT PROCESS
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The present patent application relates to a cosmetic or dermatological composition comprising, in a cosmetically or dermatologically acceptable medium, a polymer comprising: (a) a polymer backbone that may be obtained by reaction: of a polyol comprising 3 to 6 hydroxyl groups;of a monocarboxylic acid containing 6 to 32 carbon atoms;of a polycarboxylic acid comprising at least two carboxylic groups COOH, and/or of a cyclic anhydride such as a polycarboxylic acid and/or of a lactone comprising at least one carboxylic group COOH; and(b) at least one junction group linked to the said polymer backbone and capable of establishing H bonds with one or more partner junction groups, each pairing of a junction group involving at least three H (hydrogen) bonds. The patent application also concerns a cosmetic treatment process using the said composition.
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- Sensitizer/Initiator Combination for Negative-Working Thermal-Sensitive Compositions Usable for Lithographic Plates
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The radiation-sensitive composition and the negative working imageable element include a cationic IR absorber with tetraarylborate counteranion and an onium initiator with tetraarylborate counteranion. The use of these components provides high imaging sensitivity, good shelflife and high print run length.
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- PROCESS FOR PRODUCTION OF ISOCYANATE, ISOCYANATE PRODUCED BY THE PROCESS, AND USE OF THE ISOCYANATE
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An isocyanate has been widely used as a starting material for the production of a polyurethane material, a polyisocyanurate material or the like which is suitably applicable to the field of optical materials. Disclosed is a process for producing an isocyanate which includes a step for producing the isocyanate in the form of a hydrochloride with improved productivity. A process for producing a linear or cyclic aliphatic isocyanate comprising the step of reacting a linear or cyclic aliphatic amine with hydrogen chloride to yield a hydrochloride of the linear or cyclic aliphatic amine, the step being performed under a pressure higher by 0.01 MPa or more than the atmospheric pressure.
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Page/Page column 9-10; 12-17
(2008/06/13)
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- METHOD FOR PRODUCING ISOCYANATE COMPOUND
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The present invention relates to a method for preparing an isocyanate compound by introducing phosgene into an organic solvent solution of a carbonate of a corresponding amine compound and reacting the carbonate of the amine compound with phosgene, characterized in that the introduction of phosgene into the organic solvent solution of the carbonate is initiated at a temperature equal or lower than the temperature at which the carbonate is decomposed. According to the present invention, there is provided a method for advantageously preparing a less colored isocyanate compound industrially.
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Page/Page column 6
(2010/11/24)
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- Helical supramolecular aggregates based on ureidopyrimidinone quadruple hydrogen bonding
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A series of mono- and bi-functional compounds 2-7, based on the ureido pyrimidinone quadruple hydrogen bonding unit, was prepared to study the mode of aggregation of these compounds in the bulk and in solution. Compounds 2-7 exhibit thermotropic liquid crystalline properties, as evidenced by differential scanning calorimetry and optical polarization microscopy. The presence of an ordered hexagonal discotic (Dho) phase of 2a was confirmed by X-ray diffraction on an aligned sample. In chloroform, the bi-functional compounds form cyclic dimers at millimolar concentrations, and these dimers exist in equilibrium with linear species above a critical concentration, which may be from 6 mM to greater than 260 mM, depending on the structure of the spacer. Circular dichroism measurements in chloroform did not show a Cotton effect. Dodecane solutions of compounds 3, 4b, and 7b display a Cotton effect at the absorption band of the phenyl-pyrimidinone unit. Amplification of chirality was observed in mixtures of 7a and 7b, but not in mixtures of 4a and 4b, indicating that 7a and 7b form mixed polymeric aggregates with a helical architecture in dodecane solution, whereas 4a and 4b do not. The Cotton effect is lost upon increasing the temperature. Half of the helicity is lost at 25°C for 3 and at 60°C for 4b, suggesting that 3, bearing the shorter spacer, forms less stable columns than 4b. Compound 7b loses half of its helicity at 45°C. Compounds 2b, 5, and 6 do not exhibit helical organization, as evidenced by the absence of Cotton effects.
- Hirschberg, J. H. K. Ky,Koevoets, Rolf A.,Sijbesma, Rint P.,Meijer
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p. 4222 - 4231
(2007/10/03)
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- Novel carbamates as potent histamine H3 receptor antagonists with high in vitro and oral in vivo activity
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The known histamine H3 receptor antagonists burimamide, thioperamide, clobenpropit, and a related homohistamine thioamide derivative were taken as templates in search for new leads. Novel histamine H3 receptor antagonists structurally described as carbamate derivatives of 3-(1H-imidazol-4- yl)propanol were prepared in high yields by treatment of the alcohol with corresponding isocyanates or carbamoyl chlorides and investigated for their H3 receptor antagonist activity. Different chain lengths and various substituents possessing different electronic and steric parameters were introduced and structure-activity relationships established. In different functional tests, the new antagonists showed high H3 receptor antagonist potencies in vitro (-log K(i) values of 6.4-8.4) at synaptosomes of rat cerebral cortex and low activities at histamine H1 and H2 receptor subtypes. They were also screened for their central in vivo activity in mice after peroral administration. The most promising compounds (2, 16, 19) showed ED50 values of about 1-2 mg/kg and thus are potential drugs for the therapy of H3 receptor dependent diseases. Some of the novel carbamate derivatives are H3 receptor selective compounds with high in vitro and in vivo activity.
- Stark, Holger,Purand, Katja,Ligneau, Xavier,Rouleau, Agnès,Arrang, Jean-Michel,Garbarg, Monique,Schwartz, Jean-Charles,Schunack, Walter
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p. 1157 - 1163
(2007/10/03)
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- Process for producing xylylene diisocyanate
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Xylylene diisocyanate is produced in higher space-time yield with higher selectivity by thermal decomposition of xylylene dicarbamate as an urethane compound, i.e. by subjecting the urethane compound to reactive distillation with a thermal decomposition catalyst of at least one of metals selected from antimony and tin or their compounds in the presence of an inert solvent having a higher boiling point than that of the resulting xylylene diisocyanate under reduced pressure of 1 to 500 mmHg and at 150° to 350° C. and then subjecting the resulting reaction products as distillates to partial condensation outside the reactive distillation system, thereby separately recovering the resulting alcohol and xylylene diisocyanate.
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- Alkylation of Nitrocyanamide. A New Synthesis of Isocyanates
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Thirteen alkyl halides (primary, secondary, and tertiary aliphatic including alicyclic, aralkyl, and heteroalkyl systems) and certain non-vicinal dihalides on treatment with silver nitrocyanamide are converted into the corresponding isocyanates (63-95percent).Intermediate alkylnitrocyanamides, spectroscopically detected, thermolysed (-20-80 deg C) to the expected isocyanates.In certain examples silver nitrocyanamide is generated in situ from sodium nitrocyanamide and silver nitrate.Silver nitrocyanamide does not react with cyclopropyl bromide, acetyl chloride, toluene-p-sulphonyl chloride, phenacyl bromide and 2-bromomethyldioxolane (27), and the ethylene acetal (28) of 1-bromo-4-iodopentacyclo-nonan-9-one.Silver nitrocyanamide reacts with 4,6-bis(bromomethyl)-3,7-dimethyl-1,5-diazabicyclo3.3.0)octane-2,8-dione (26), to give an intractable mixture.Vicinal dihalides give erratic results without detectable formation of vicinal di-isocyanates: unisolated 2-bromoethyl isocyanate (tentative assignment) has been detected in a product mixture from ethylene dibromide; an expected rearrangement during the reaction with 1,2-dibromocyclobutane, brought about the formation of 4-bromobut-3-enyl isocyanate isolated as ethyl 4-bromobut-3-enylcarbamate in low yield; and 1,2-dibromocyclohexane gives 2-bromocyclohexyl isocyanate isolated as ethyl N-(2-bromocyclohexyl)-carbamate in low yield.
- Boyer, Joseph H.,Manimaran, Thanikavelu,Wolford, Lionel T.
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p. 2137 - 2140
(2007/10/02)
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- Catalytic oxidation of formamides to form isocyanates
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This invention relates to a process for preparing isocyanates from formamides wherein a formamide corresponding to the formula R--NHCHO)n, where R is an organic group and n is 1 or 2, is oxidized with an oxygen containing gas at a temperature in the range of 300° C. to 600° C. in the presence of a catalytic amount of copper and/or one or more metals of the Groups IB and VIII of the 5th and 6th period of the Periodic System of Elements to yield the corresponding isocyanate R (NCO)n where R and n have the same meaning as above, and the resultant gaseous isocyanate containing reaction mixture is subjected to a separation process to separate the product isocyanate from water of reaction.
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