Patents by Inventor Yasuo Tokitoh
Yasuo Tokitoh has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
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Patent number: 6929787Abstract: A composite which is easy to manufacture and has excellent catalytic activity and mechanical strength is obtained by heating and drying a mixture of a carrier in powder form and a metal hydroxide in powder form or in molten form under a gas flow or under reduced pressure. The composite can be used as a catalyst for the isomerization of an olefin or for the oxidation reaction of an alcohol.Type: GrantFiled: February 13, 2002Date of Patent: August 16, 2005Assignee: Kuraray Co., Ltd.Inventor: Yasuo Tokitoh
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Publication number: 20020111269Abstract: A composite which is easy to manufacture and has excellent catalytic activity and mechanical strength is obtained by heating and drying a mixture of a carrier in powder form and a metal hydroxide in powder form or in molten form under a gas flow or under reduced pressure. The composite can be used as a catalyst for the isomerization of an olefin or for the oxidation reaction of an alcohol.Type: ApplicationFiled: February 13, 2002Publication date: August 15, 2002Applicant: KURARAY CO. LTD.Inventor: Yasuo Tokitoh
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Patent number: 5994590Abstract: A process for producing 7-octen-1-al by isomerization of 2,7.octadien-1-ol by feeding 2,7-octadien-1-ol and hydrogen to a reaction zone in the presence of a copper catalyst while controlling the molar ratio of 2,7-octadien-1-ol to hydrogen within a range of 99/1 to 75/25, and effecting isomerization in the gaseous phase. This process ensures a high yield, a high selectivity and stable operation over a long period of time.Type: GrantFiled: September 30, 1998Date of Patent: November 30, 1999Assignee: Kuraray Co., Ltd.Inventors: Tomoyasu Tsuda, Yasuo Tokitoh, Kazunori Watanabe, Takashi Hori
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Patent number: 5684167Abstract: 2-Hydroxy-4-methyltetrahydrofuran is prepared by reacting 2-methyl-2-propen-1-ol with hydrogen and carbon monoxide in the presence of:(a) a rhodium compound, and(b) tris(substituted aryl)phosphite having an electronic parameter (.nu.-value) of 2080 to 2090 cm.sup.-1 and a steric parameter (.theta.-value) of 135.degree. to 190.degree. and having formula (1): ##STR1## wherein R.sup.1, R.sup.2 and R.sup.3 independently of each other represent a substituted aryl group having at least 7 carbon atoms, the ratio of said rhodium compound (a) to said tris(substituted aryl) phosphite (b) ranging from 110 to 1000 moles per 1 gram atom of rhodium in said rhodium compound (a).Type: GrantFiled: June 7, 1996Date of Patent: November 4, 1997Assignee: Kuraray Co., Ltd.Inventors: Toshihiro Omatsu, Takashi Onishi, Yasuo Tokitoh
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Patent number: 5434311Abstract: In hydroformylation comprising allowing an ethylenically unsaturated compound to react with carbon monoxide and hydrogen in the presence of a catalyst to convert it into a corresponding aldehyde, the catalyst is a rhodium-containing catalyst comprising;(a) a rhodium compound;(b) an organic phosphorus compound having at least one tertiary amine residual group and at least one tertiary phosphorus residual group, having the ability of coordination to said rhodium compound; and optionally(c) an acidic compound with which at least part of the tertiary amine residual group of the organic phosphorus compound is converted into ammonium ions.Type: GrantFiled: April 19, 1994Date of Patent: July 18, 1995Assignee: Kuraray Co., Ltd.Inventors: Toshihiro Omatsu, Yasuo Tokitoh
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Patent number: 5414138Abstract: A process for producing 2-formyl-1,4-butanediol comprises effecting reaction of 2-butene-1,4-diol with hydrogen and carbon monoxide in the presence of:(a) a rhodium compound,(b) a tris(substituted aryl) phosphite having an electronic parameter, .nu.-value, of 2,080 to 2,090 cm.sup.-1 and a steric parameter, .theta.-value, of 135.degree. to 190.degree. and being represented by the formula P(OR).sub.3wherein each of R's, which may be the same or different, represents a substituted aryl group having at least 7 carbon atoms, and(c) a bis (diphenylphosphino) alkane represented by the formula Ph.sub.2 P-(CH.sub.2)n-PPh.sub.2 where n n is an integer of 2 to 6, andat a temperature of not more than 80.degree. C.Type: GrantFiled: June 2, 1994Date of Patent: May 9, 1995Assignee: Kuraray Company Ltd.Inventors: Toshihiro Omatsu, Yasuo Tokitoh
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Patent number: 5118885Abstract: An improved process for producing octa-2,7-dien-1-ol which comprises reacting butadiene with water in an aqueous sulfolane solution containing a carbonate and/or bicarbonate of a monodentate tertiary amine in the presence of a palladium compound and a phosphonium salt.Type: GrantFiled: December 27, 1990Date of Patent: June 2, 1992Assignee: Kuraray Co., Ltd.Inventors: Yasuo Tokitoh, Tamio Higashi, Kenichi Hino, Masami Murasawa, Noriaki Yoshimura
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Patent number: 5100854Abstract: Novel phosphonium salts of the general formula ##STR1## wherein R.sup.1 and R.sup.2 each is a hydrogen atom or a hydrocarbon group of 1 to 12 carbon atoms which may optionally be substituted; R.sup.3 is a hydrogen atom or a hydrocarbon group of 1 to 5 carbon atoms which may optionally be substituted; R.sup.4, R.sup.5 and R.sup.6 each is a hydrocarbon group of 1 to 8 carbon atoms which may optionally be substituted; X is a hydroxyl group, a hydroxycarbonyloxy group or a lower alkylcarbonyloxy group, and processes for production of the salts are described. Telomerization catalysts containing said phosphonium salts and processes for production of straight-chained alkadienyl compounds using the same catalysts are also provided.Type: GrantFiled: November 30, 1990Date of Patent: March 31, 1992Assignee: Kuraray Co., Ltd.Inventors: Toshihiko Maeda, Yasuo Tokitoh, Noriaki Yoshimura
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Patent number: 5057631Abstract: Butadiene and water are reacted continuously in the presence of a solvent capable of dissolving both reactants and a palladium catalyst with the mole ratio of butadiene to the reaction product octa-2,7-dien-1-ol in the reaction mixture being maintained at 0.6 or more. By this process, octa-2,7-dien-1-ol can be produced continuously without reductions in reaction rate and selectivity and with decreased insoluble polymer formation.Type: GrantFiled: February 12, 1990Date of Patent: October 15, 1991Assignee: Kuraray Co., Ltd.Inventors: Yasuo Tokitoh, Noriaki Yoshimura
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Patent number: 4992609Abstract: Novel phosphonium salts of the general formula ##STR1## wherein R.sup.1 and R.sup.2 each is a hydrogen atom or a hydrocarbon group of 1 to 12 carbon atoms which may optionally be substituted; R.sup.3 is a hydrogen atom or a hydrocarbon group of 1 to 5 carbon atoms which may optionally be substituted; R.sup.4, R.sup.5 and R.sup.6 each is a hydrocarbon group of 1 to 8 carbon atoms which may optionally be substituted; X is a hydroxyl group, a hydroxycarbonyloxy group or a lower alkylcarbonyloxy group, and processes for production of the salts are described. Telomerization catalysts containing said phosphonium salts and processes for production of straight-chain alkadienyl compounds using the same catalysts are also provided.Type: GrantFiled: March 13, 1990Date of Patent: February 12, 1991Assignee: Kuraray Co., Ltd.Inventors: Toshihiko Maeda, Yasuo Tokitoh, Noriaki Yoshimura
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Patent number: 4935488Abstract: Novel trimethylolheptanes having three highly reactive hydroxyl groups are provided. They are useful as raw materials for the production of polyesters for use in or as raw materials or modifiers for paints, inks, adhesives, coating compositions and molding resins. Uses for the trimethylolheptanes are also provided.Type: GrantFiled: April 20, 1989Date of Patent: June 19, 1990Assignee: Kurary Company, Ltd.Inventors: Toshihiro Omatsu, Yasuo Tokitoh, Noriaki Yoshimura, Masao Ishida, Makoto Yano, Koji Hirai, Yoichi Matsumoto, Keiji Kubo
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Patent number: 4927960Abstract: Novel phosphonium salts of the general formula ##STR1## wherein R.sup.1 and R.sup.2 each is a hydrogen atom or a hydrocarbon group of 1 to 12 carbon atoms which may optionally be substituted; R.sup.3 is a hydrogen atom or a hydrocarbon group of 1 to 5 carbon atoms which may optionally be substituted; R.sup.4, R.sup.5 and R.sup.6 each is a hydrocarbon group of 1 to 8 carbon atoms which may optionally be substituted; X is a hydroxyl group, a hydroxycarbonyloxy group or a lower alkylcarbonyloxy group, and processes for production of the salts are described. Telomerization catalysts containing said phosphonium salts and processes for production of straight-chain alkadienyl compounds using the same catalysts are also provided.Type: GrantFiled: June 24, 1988Date of Patent: May 22, 1990Assignee: Kuraray Company, Ltd.Inventors: Toshihiko Maeda, Yasuo Tokitoh, Noriaki Yoshimura
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Patent number: 4871880Abstract: A hydroformylation process is provided which comprises reacting a compound of the general formulaCH.sub.2 .dbd.CH--CH.sub.2 --A--CH.sub.2 --Xwherein X is a hydroxyl or formyl group and A is a group of the formula--(CH.sub.2).sub.n -- or --(CH.sub.2).sub.m --CH.dbd.CH--in which n is an integer of 3-8 and m is an integer of 0-5, with a mixture of hydrogen and carbon monoxide in the presence of a rhodium compound and a specific tris(substituted phenyl) phosphite.Type: GrantFiled: May 26, 1988Date of Patent: October 3, 1989Assignee: Kuraray Co., Ltd.Inventors: Toshihiro Omatsu, Yasuo Tokitoh, Noriaki Yoshimura
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Patent number: 4861922Abstract: There is disclosed a method of hydroformylating 3-methyl-3-buten-1-ol and analogs thereof with carbon monoxide and hydrogen in the presence of a rhodium compound free from modification by a ligand containing an element belonging to the group V of the periodic table as well as a method of producing 3-methylpentane-1,5-diol and .beta.-methyl-.delta.-valerolactone using such hydroformylation product.Type: GrantFiled: February 11, 1987Date of Patent: August 29, 1989Assignee: Kuraray Company, Ltd.Inventors: Yasuo Tokitoh, Noriaki Yoshimura
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Patent number: 4808756Abstract: The method for producing .alpha.,.omega.-dialdehydes from .alpha.,.omega.-diolefins or .alpha.,.omega.-alkenals in good yield and with high efficiency. The expensive rhodium catalyst for hydroformylation can be reused without any substantial attrition of activity. Moreover, since the loses of the catalyst, monodentate phosphine and sulfolane used in the hydroformylation reaction are minimal, the method is commercially advantageous.Type: GrantFiled: October 6, 1987Date of Patent: February 28, 1989Assignee: Kuraray Co., Ltd.Inventors: Yasuo Tokitoh, Noriaki Yoshimura
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Patent number: 4808737Abstract: The hydroformylation of 3-methyl-3-buten-1-ol with hydrogen and carbon monoxide, when carried out under relatively mild conditions, gives 2-hydroxy-4-methyltetrahydropyran (MHP) in high rate of reaction and in high selectivity even in a very low rhodium catalyst concentration. MHP is useful as a starting material for the production of 3-methyl-1,5-pentanediol and .beta.-methyl-.delta.-valerolactone which are in turn usable as raw materials for producing polyesters and polyurethanes. The process according to the invention can give such MHP advantageously from the industrial viewpoint and has very great industrial utility.Type: GrantFiled: October 22, 1986Date of Patent: February 28, 1989Assignee: Kuraray Co., Ltd.Inventors: Noriaki Yoshimura, Yasuo Tokitoh
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Patent number: 4663468Abstract: There is disclosed a method of hydroformylating 3-methyl-3-buten-1-ol and analogs thereof with carbon monoxide and hydrogen in the presence of a rhodium compound free from modification by a ligand containing an element belonging to the group V of the periodic table as well as a method of producing 3-methylpentane-1,5-diol and .beta.-methyl-.delta.-valerolactone using such hydroformylation product.Type: GrantFiled: March 12, 1985Date of Patent: May 5, 1987Assignee: Kuraray Company, Ltd.Inventors: Yasuo Tokitoh, Noriaki Yoshimura
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Patent number: 4271320Abstract: An industrially suitable process for producing a higher carbonyl compound by the oxidation of an olefinic compound having at least six carbon atoms is provided. Said improved process comprises oxidizing the olefinic compound in aqueous medium containing palladium or salt thereof and a copper salt in the presence of a specific water-soluble polyoxyalkylene compound in an amount of from about 1/4 to about 3 parts by weight per 1 part by weight of water contained in the reaction mixture. The improvement is demonstrated in terms of yield, selectivity, separation of the product, and recycle of the catalyst.Type: GrantFiled: August 31, 1979Date of Patent: June 2, 1981Assignee: Kuraray Co., Ltd.Inventors: Yasuo Tokitoh, Noriaki Yoshimura, Masuhiko Tamura