Patents Represented by Attorney Marvin Turken
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Patent number: 5166418Abstract: A method is provided for the preparation of ibuprofen by carbonylating 1-(4'-isobutylphenyl)ethanol (IBPE) with carbon monoxide comprising initially a reaction mixture comprising IBPE, ibuprofen and a catalyst for the carbonylation with carbon monoxide under conditions to initiate the reaction, and continuing to feed carbon monoxide to the composition to produce the desired yield of ibuprofen. Preferably the catalyst comprises palladium and a monodentate phosphine ligand. The presence of ibuprofen in the feed composition when the reaction is initiated with CO makes it possible to obtain high selectivities to ibuprofen with substantially complete conversion of IBPE at much shorter reaction times than if no ibuprofen is present initially.Type: GrantFiled: December 4, 1991Date of Patent: November 24, 1992Assignee: Hoechst Celanese CorporationInventors: Joel D. Hendricks, Graham N. Mott
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Patent number: 5157142Abstract: A process is provided for preparing N-acyl-aminothiophenols, e.g., N-acetyl-para-aminothiophenol, or aminothiophenols, e.g., para-aminothiophenol, by reacting a hydroxy aromatic ketone, e.g., 4-hydroxyacetophenone (4-HAP), with hydroxylamine or a hydroxylamine salt, to form the oxime of the ketone, subjecting the oxime to a Beckmann rearrangement in the presence of a catalyst to form the N-acyl-hydroxy aromatic amine, e.g., N-acetyl-para-aminophenol (APAP), reacting the N-acyl-hydroxy aromatic amine with an N,N-di (organo) thiocarbamoyl halide, e.g., N,N-dimethylthiocarbamoyl chloride, to form an O-(N-acyl-aminoaryl)-N,N-di (organo) thiocarbamate, e.g., O-(N-acetyl-para-aminophenyl)-N,N-dimethylthiocarbamate, pyrolytically rearranging the O-(N-acyl-aminoaryl)-N,N-di (organo) thiocarbamate to form an S-(N-acyl-aminoaryl)-N,N-di (organo) thiocarbamate, e.g., S-(N-acetyl-para-aminophenyl)-N,N-dimethylthiocarbamate, and hydrolyzing the latter compound to obtain the N-acyl aminothiophenol or aminothiophenol.Type: GrantFiled: June 17, 1986Date of Patent: October 20, 1992Assignee: Hoechst Celanese CorporationInventor: Kenneth G. Davenport
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Patent number: 5151540Abstract: A method is provided for preparing N-acylaminothiophenols, e.g., N-acetyl-para-aminothiophenol, or aminothiophenols, e.g., para-aminothiophenol, or N,S-diacylaminothiophenols, e.g., N,S-diacetyl-para-aminothiophenol, by reacting any of certain sulfur-containing ketones, viz., an S-(acylaryl) N,N-di(organo)thiocarbamate, e.g., S-(4'-acetophenyl)-N,N-dimethylthiocarbamate, an acylthiophenol acylate ester, e.g., 4-acetothiophenol acetate, or a free acylthiophenol, e.g., 4-acetothiophenol with hydroxylamine or a hydroxylamine salt, to form the oxime of the ketone, subjecting the oxime to a Beckmann rearrangement in the presence of a catalyst to form an S-(N-acyl-aminoaryl) N,N-di(organo)thiocarbamate, e.g., S-(N-acetyl-para-aminophenyl) N,N-dimethylthiocarbamate, an N,S-diacylaminothiophenol, e.g., N,S-diacetyl-paraaminothiophenol, or an N-acyl aminothiophenol, e.g., N-acetyl-para-aminothiophenol, respectively.Type: GrantFiled: November 26, 1986Date of Patent: September 29, 1992Assignee: Hoechst Celanese CorporationInventors: Mohammad Aslam, Kenneth G. Davenport
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Patent number: 5068448Abstract: A continuous process is provided for the production of 4'-isobutylacetophenone (4-IBAP) comprising feeding liquid hydrogen fluoride (HF) and an acetylating agent into an extractor-reactor to form a first, HF-rich phase containing the acetylating agent, feeding isobutylbenzene (IBB) to the extractor-reactor to form a second, IBB-rich phase which is contacted with said first, HF-rich phase in a manner such that the acetylating agent reacts with IBB to form 4-IBAP which is extracted into the first, HF-rich phase, and a light IBB-rich second phase containing the bulk of unreacted IBB, externally recycling said second, IBB-rich phase to the IBB feed point in combination with fresh IBB to make up for IBB consumed in the reaction and that and dissolved in the HF-rich phase, and withdrawing HF-rich phase containing 4-IBAP from the extractor-reactor.Type: GrantFiled: October 5, 1990Date of Patent: November 26, 1991Assignee: Hoechst Celanese CorporationInventors: Daniel D. Lindley, Thomas A. Curtis, Timothy R. Ryan, Edward M. de la Garza, Charles B. Hilton, Thomas M. Kenesson
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Patent number: 5045607Abstract: There are provided new moldable blends of a normally crystalline acetal polymer and a normally non-crystalline elastomeric copolymer of about 15 to 45 mol %, preferably about 25 to 35 mol % of trioxane, about 55 to 85 %, preferably about 65 to 75 mol % of 1,3-dioxolane, said mol percents based on the total of trioxane and 1,3-dioxolane, and about 0.005 to 0.15 wt. %, preferably about 0.05 to 0.12 wt. % of 1,4-butanediol diglycidyl ether or butadiene diepoxide as a bifunctional monomer, based on the total weight of copolymer.Type: GrantFiled: April 5, 1989Date of Patent: September 3, 1991Assignee: Hoechst Celanese Corp.Inventors: Kurt F. Wissbrun, Hongkyu Kim, George L. Collins, Diane Terrone
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Patent number: 5041657Abstract: A method is provided for preparing aromatic acetamides comprising reacting an aryl methyl ketone containing the same number of carbon atoms as the aromatic acetamide, with sulfur and ammonia under substantially anhydrous conditions. The method is particularly useful for the preparation of 4-hydroxyphenylacetamide from 4-hydroxyacetophenone.Type: GrantFiled: July 19, 1990Date of Patent: August 20, 1991Assignee: Hoechst Celanese CorporationInventor: Graham N. Mott
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Patent number: 5041666Abstract: A method is provided for the production of 3,3', 4,4'-tetraaminobiphenyl (TAB) from biphenyl comprising the following steps:1) acetylating the biphenyl in the presence of an appropriate Friedel-Crafts catalyst to obtain 4,4'-diacetylbiphenyl (DAcB);2) oximating the DAcB to form DAcB dioxime;3) subjecting the dioxime to a double Beckmann rearrangement to obtain N,N-diacetylbenzidine (DiAcBz);4) nitrating the DiAcBz to obtain 3,3'-dinitro-N,N-diacetylbenzidine (DNAcBz)5) removing the acetyl groups of the DNAcBz by basic hydrolysis to form 3,3'-dinitrobenzidine (DNB); and6) reducing the nitrate groups of the DNB to form TAB.Type: GrantFiled: August 6, 1987Date of Patent: August 20, 1991Assignee: Hoechst Celanese CorporationInventors: Bennett C. Ward, Wilson B. Ray, Charles B. Hilton, Anthony J. East, Kenneth G. Davenport
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Patent number: 5012007Abstract: A method is provided for the production of 2,2-diorgano-1-indanones, e.g., 2,2-dimethyl-1-indanone, by reacting an alcohol which is the corresponding (diorganosubstitutedmethyl)phenyl(or substitutedphenyl)carbinol, e.g., 2-methyl-1-phenyl-1-propanol, with carbon monoxide in the presence of a Lewis acid catalyst, e.g., hydrogen fluoride, with any substituents on the phenyl group of the alcohol being hydroxy or organo. The foregoing reaction is preferably integrated with the preparation of the feed alcohol by reducing the corresponding (diorganosubstitutedmethyl)phenyl(or substitutedphenyl)ketone, e.g., isobutyrophenone, with a reducing agent containing available hydrogen, e.g., sodium borohydride, or with hydrogen gas in the presence of a hydrogenation catalyst.Type: GrantFiled: October 5, 1989Date of Patent: April 30, 1991Inventor: Varadaraj Elango
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Patent number: 5001215Abstract: A process is described for producing shapable aromatic polyesters derived from 1,3-bis(p-carboxyphenoxy)propane (CPP) and a dihydric phenol comprising forming a mixed anhydride of CPP with a lower monocarboxylic acid containing at least 2 carbon atoms, e.g., acetic acid, and subsequently polymerizing said mixed anhydride with said dihydric phenol or a reactable diester of said dihydric phenol, to obtain said aromatic polyester. The process is capable of producing aromatic polyesters as described having a glass transition temperature of at least about 70.degree. C.Type: GrantFiled: November 2, 1989Date of Patent: March 19, 1991Assignee: Hoechst Celanese Corp.Inventor: Balaram Gupta
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Patent number: 4990681Abstract: A method is provided for separating hydrogen fluoride (HF) from a mixture comprising HF complexed with an aromatic ketone in which the keto carbon atom is directly bonded to an aromatic ring carbon atom, e.g., 4-isobutylacetophenone, by adding a carboxylic acid anhydride, e.g., acetic anhydride, to the mixture while maintaining the mixture at conditions sufficient to sustain a reaction between the anhydride and the HF to form the corresponding acyl fluoride, e.g., acetyl fluoride, and carboxylic acid, e.g., acetic acid, and separating the acyl fluoride from the mixture. The method is conveniently carried out in a stripping column near the top of which the mixture comprising aromatic ketone and HF is fed and below which the anhydride is fed. Between these feed points, the uncomplexed HF is stripped from the mixture, while below the anhydride feed point or points, the anhydride reacts with the complexed HF to form the acyl fluoride which is stripped from the mixture, and the carboxylic acid.Type: GrantFiled: December 4, 1989Date of Patent: February 5, 1991Inventors: Thomas A. Curtis, Timothy R. Ryan, Daniel D. Lindley
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Patent number: 4973752Abstract: A novel process is disclosed for the prevention of the formation of chlorinated by-products during the Beckmann rearrangement of 4-hydroxyacetophenone oxime to APAP utilizing thionyl chloride as catalyst, by the addition of an inorganic iodide such as potassium iodide to the Beckmann rearrangement reactor.Type: GrantFiled: April 24, 1989Date of Patent: November 27, 1990Inventor: Olan S. Fruchey
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Patent number: 4954400Abstract: There are provided new articles comprising elements having surfaces bonded together with a bonding resin which is an elastomeric copolymer of about 15 to 45 mol %, preferably about 25 to 35 mol % trioxane, about 55 to 85 mol %, preferably about 65 to 75 mol % of 1,3-dioxolane, said mol percents based on the total of trioxane and 1,3-dioxolane, and about 0.005 to 0.15 wt. %, preferably about 0.05 to 0.12 wt. % of 1,4-butanediol diglycidyl ether or butadiene diepoxide as a bifunctional monomer, based on the total weight of copolymer. Preferably, at least one of said surfaces, and more preferably at least two of said surfaces bonded to each other are of a crystalline acetal polymer comprising at least 85 mol % of polymerized oxymethylene units.Type: GrantFiled: October 11, 1988Date of Patent: September 4, 1990Assignee: Hoechst Celanese Corp.Inventors: George L. Collins, Hongkyu Kim, William M. Pleban
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Patent number: 4937319Abstract: A process is described for producing shapable aromatic polyesters derived from bisphenol A and a dicarboxylic acid comprising isophthalic acid, terephthalic acid, or a mixture of the two, comprising forming a mixed anhydride of said dicarboxylic acid and acetic acid, and subsequently reacting said mixed anhydride with bisphenol A while drawing off acetic acid by-product to obtain said aromatic polyester.Type: GrantFiled: June 23, 1989Date of Patent: June 26, 1990Assignee: Hoechst Celanese Corp.Inventors: Balaram Gupta, John R. Costanza
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Patent number: 4937312Abstract: There are provided new elastomeric copolymers of about 15 to 45 mol %, preferably about 25 to 35 mol % trioxane, about 55 to 85 mol %, preferably about 65 to 75 mol % of 1,3-dioxolane, said mol percents based on the total of trioxane and 1,3-dioxolane, and about 0.005 to 0.15 wt. %, preferably about 0.05 to 0.12 wt. % of 1,4-butanediol diglycidyl ether or butadiene diepoxide as a bifunctional monomer, based on the total weight of copolymer. The elastomeric copolymers may be prepared by mixing said monomers in a substantially dry state and under an inert atmosphere with a cationic polymerization catalyst, e.g., p-nitrobenzenediazonium tetrafluoroborate. The elastomeric copolymers have a strong interaction with moldable, crystalline acetal polymers comprising at least 85 mol % of polymerized oxymethylene units and may be used as a blending agent with such crystalline acetal polymers or as a bonding agent to improve the adhesiveness of the crystalline acetal polymer to other materials.Type: GrantFiled: December 11, 1989Date of Patent: June 26, 1990Assignee: Hoechst Celanese Corp.Inventors: George L. Collins, Kurt F. Wissbrun, Hongkyu Kim
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Patent number: 4929694Abstract: There are provided novel copolymers of a p-mercaptostyrene ester, e.g., the acetate, with at least one comonomer selected from the group consisting of styrene, N-methylmaleimide, maleic anhydride and p-acetoxystyrene. These copolymers may be hydrolyzed to produce corresponding copolymers of p-mercaptostyrene with at least one comonomer selected from the group consisting of styrene, N-methylmaleimide, maleic acid and p-vinylphenol. The copolymers have application as heavy metal sequestering agents in various forms and structures.Type: GrantFiled: May 4, 1989Date of Patent: May 29, 1990Assignee: Hoechst Celanese CorporationInventors: Mohammad Aslam, Richard Vicari, Kenneth G. Davenport
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Patent number: 4898925Abstract: There are provided new elastomeric copolymers of about 15 to 45 mol %, preferably about 25 to 35 mol % trioxane, about 55 to 85 mol %, preferably about 65 to 75 mol % of 1,3-dioxolane, said mol percents based on the total of trioxane and 1,3-dioxolane, and about 0.005 to 0.15 wt. %, preferably about 0.05 to 0.12 wt. % of 1,4-butanediol diglycidyl ether or butadiene diepoxide as a bifunctional monomer, based on the total weight of copolymer. The elastomeric copolymers may be prepared by mixing said monomers in a substantially dry state and under an inert atmosphere with a cationic polymerization catalyst, e.g, p-nitrobenzenediazonium tetrafluoroborate. The elastomeric copolymers have a strong interaction with moldable, crystalline acetal polymers comprising at least 85 mol % of polymerized oxymethylene units and may be used as a blending agent with such crystalline acetal polymers or as a bonding agent to improve the adhesiveness of the crystalline acetal polymer to other materials.Type: GrantFiled: September 12, 1988Date of Patent: February 6, 1990Assignee: Hoechst Celanese CorporationInventors: George L. Collins, Kurt F. Wissbrun, Hongkyu Kim
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Patent number: 4894482Abstract: A process is provided for removing water from a mixture of hydrogen fluoride (HF), a carboxylic acid, e.g., acetic acid, and water by extractive distillation in the presence of a Lewis base as solvent, which does not azeotrope with water, forms bonds with the HF and carboxylic acid which can be broken by heat and has a boiling point at atmospheric pressure at least about 20.degree. C. above that of the carboxylic acid, e.g., N-methyl-2-pyrrolidone, and taking off an overhead vapor comprising a major proportion of the water in said mixture. The extractive distillation may be advantageously integrated in an overall process with the production of an aromatic ketone, e.g., 4-hydroxyacetophone, by the Friedel-Crafts acylation of an aromatic compound, e.g., phenol, with the carboxylic acid, using HF as catalyst, to produce a product mixture comprising the aromatic ketone, HF, carboxylic acid and water, and the removal of aromatic ketone from the product mixture by means of a solvent assisted distillation.Type: GrantFiled: December 6, 1988Date of Patent: January 16, 1990Assignee: Hoechst Celanese CorporationInventors: Daniel D. Lindley, Carl D. Murphy
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Patent number: 4876368Abstract: A process is provided for the production of a monohydroxy monocyclic acetal, e.g., trimethylolpropane cyclic formal, of a trihydroxy alcohol, e.g., trimethylolpropane, and an aldehyde, e.g., formaldehyde, by subjecting a "heavier condensation product" of the trihydroxy alcohol and the aldehyde than the desired cyclic acetal, i.e., one having a higher molecular weight and boiling point, to acetal formation conditions. In a preferred embodiment, the product of reaction of the trihydroxy alcohol and aldehyde is treated to remove the desired monohydroxy monocyclic acetal product and at least part of the remainder comprising the heavier condensation product is recycled to the reaction together with a flesh supply of trihydroxy alcohol and aldehyde. The monohydroxy monocyclic acetal product may be further reacted to obtain a desired ester, e.g. trimethylolpropane cyclic formal acrylate, such as by transesterifying the acetal with a low boiling ester of the esterifying acid, e.g.Type: GrantFiled: May 24, 1988Date of Patent: October 24, 1989Assignee: Hoechst Celanese CorporationInventors: Jerry A. Broussard, Wayne C. Fuqua, James H. George
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Patent number: 4868274Abstract: There are provided novel homopolyanhydrides of carboxyaryloxyalkanoic acids, e.g. p-carboxyphenoxyacetic acid or 6-(p-carboxyphenoxy)hexanoic acid, capable of being formed into shaped articles. The homopolyanhydrides may be prepared by heating under reflux a solution of the acid monomer in acetic anhydride to form a mixed anhydride of the acid monomer and acetic acid and melt polycondensing the prepolymer by heating it under vacuum in an inert atmosphere. Due to their property of hydrolytic cleavage at predictable rates, the homopolyanhydrides are suitable as polymer matrices providing for the controlled release of an agent such as a drug.Type: GrantFiled: May 23, 1988Date of Patent: September 19, 1989Assignee: Hoechst Celanese Corp.Inventors: Balaram Gupta, Gordon W. Calundann
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Patent number: 4868265Abstract: A process is provided for preparing homopolyanhydrides or regularly alternating copolyanhydrides by condensing a bis(trimethylsilyl) ester of a dicarboxylic acid, e.g., an alkylenedicarboxylic acid such as sebacic acid or a bis(p-carboxyphenoxy)alkane such as 1,3-bis(p-carboxyphenoxy)propane, with a dicarboxylic acid chloride, e.g., an alkylenedicarboxylic acid chloride such as sebacoyl chloride or a phenylenedicarboxylic acid chloride such as terephthaloyl chloride or isophthaloyl chloride, to yield the polyanhydride and chlorotrimethylsilane as a by-product. The process may be carried out in the presence of a condensation catalyst, e.g., a highly ionized organic or inorganic fluoride, such as tetrabutylammonium fluoride.Type: GrantFiled: October 5, 1988Date of Patent: September 19, 1989Assignee: Hoechst Celanese Corp.Inventor: Balaram Gupta