Patents by Inventor Kosaku Hirota
Kosaku Hirota 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: 9255070Abstract: The subject of the present invention is to provide a method for deuteration, which can obtain a compound having an aromatic ring and/or a heterocyclic ring at an improved deuteration ratio. The present invention relates to a method for deuteration of a compound having an aromatic ring and/or a heterocyclic ring, comprising reacting the compound having an aromatic ring and/or a heterocyclic ring with a heavy hydrogen source in the presence of an activated mixed catalyst of not less than two kinds of catalysts selected from among a palladium catalyst, a platinum catalyst, a rhodium catalyst, an iridium catalyst, a ruthenium catalyst, a nickel catalyst and a cobalt catalyst.Type: GrantFiled: December 21, 2004Date of Patent: February 9, 2016Assignee: WAKO PURE CHEMICAL INDUSTRIES, LTD.Inventors: Nobuhiro Ito, Tsuneaki Maesawa, Kazushige Muto, Kosaku Hirota, Hironao Sajiki
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Patent number: 8093422Abstract: The present invention relates to a method for deuteration of a compound having an aromatic ring, using an activated catalyst, and the method comprises reacting a compound having an aromatic ring with heavy hydrogen source in the presence of an activated catalyst selected from a platinum catalyst, a rhodium catalyst, a ruthenium catalyst, a nickel catalyst and a cobalt catalyst.Type: GrantFiled: July 10, 2003Date of Patent: January 10, 2012Assignee: Wako Pure Chemical Industries, Ltd.Inventors: Nobuhiro Ito, Tsuneaki Maesawa, Kazushige Muto, Kosaku Hirota, Hironao Sajiki
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Patent number: 7795166Abstract: A functional group-selective hydrogenation catalyst is provided, which is capable of selectively hydrogenating an aliphatic carbon-carbon double bond, aliphatic carbon-carbon triple bond, aromatic formyl group or aromatic nitro group contained in an organic compound. The catalyst includes a carrier, and palladium and an organic sulfur compound supported jointly thereon.Type: GrantFiled: December 1, 2006Date of Patent: September 14, 2010Assignee: N.E. Chemcat CorporationInventors: Hironao Sajiki, Tomohiro Maegawa, Kosaku Hirota
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Patent number: 7517990Abstract: The present invention relates to a method for deuteration of a heterocyclic ring, which comprises subjecting a compound having a heterocyclic ring to sealed refluxing state in a deuterated solvent in the presence of an activated catalyst selected form a palladium catalyst, a platinum catalyst, a rhodium catalyst, a ruthenium catalyst, a nickel catalyst and a cobalt catalyst. In accordance with a method of the present invention, a hydrogen atom belonging to a heterocyclic ring of a compound having a heterocyclic ring can be very efficiently deuterated because temperature of deuteration reaction can be maintained at higher than boiling point of the solvent. Further, a method for deuteration of the present invention can be applied widely to deuteration of various compounds having a heterocyclic ring which are liable to decomposition under supercritical conditions or acidic conditions, leading to industrial and efficient deuteration of a compound having a heterocyclic ring.Type: GrantFiled: November 7, 2003Date of Patent: April 14, 2009Assignee: Wako Pure Chemical Industries, Ltd.Inventors: Nobuhiro Ito, Tsuneaki Maesawa, Kazushige Muto, Kosaku Hirota, Hironao Sajiki
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Publication number: 20080269425Abstract: The present invention is directed to provide a catalyst for reduction, which is capable of reducing even mono-substituted alkynes to alkenes and does not require the coexistence (combined use) of a toxic compound, and a method for reduction from alkynes to alkenes using the catalyst; and relates to a palladium-supported polyethyleneimine compound obtained by contacting a polyethyleneimine, a palladium compound and hydrogen gas in an oxygen-free state, a method for producing the above palladium-supported polethyleneimine compound, a catalyst for reduction comprising the above palladium-supported polyethyleneimine compound, and a method for reducing from alkynes to alkenes characterized by contacting an alkyne and hydrogen in the presence of a palladium-supported polyethyleneimine compound, which is obtained by reacting a polyethyleneimine, a palladium compound and hydrogen gas in an oxygen-tree state.Type: ApplicationFiled: December 2, 2005Publication date: October 30, 2008Applicant: WAKO PURE CHEMICAL INDUSTRIES, LTD.Inventors: Kosaku Hirota, Hironao Sajiki
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Publication number: 20080234488Abstract: The subject of the present invention is to provide a method for deuteration, which can obtain a compound having an aromatic ring and/or a heterocyclic ring at an improved deuteration ratio. The present invention relates to a method for deuteration of a compound having an aromatic ring and/or a heterocyclic ring, comprising reacting the compound having an aromatic ring and/or a heterocyclic ring with a heavy hydrogen source in the presence of an activated mixed catalyst of not less than two kinds of catalysts selected from among a palladium catalyst, a platinum catalyst, a rhodium catalyst, an iridium catalyst, a ruthenium catalyst, a nickel catalyst and a cobalt catalyst.Type: ApplicationFiled: December 21, 2004Publication date: September 25, 2008Applicant: WAKO PURE CHEMICAL INDUSTRIES, LTD.Inventors: Nobuhiro Ito, Tsuneaki Maesawa, Kazushige Muto, Kosaku Hirota, Hironao Sajiki
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Publication number: 20080145303Abstract: [PROBLEMS] To provide a method for producing heavy hydrogen gas, which enables heavy hydrogen gas to be efficiently produced from a deuterated solvent as a reaction substrate. [MEANS FOR SOLVING PROBLEMS] (1) A method for producing heavy hydrogen gas, comprising bringing a deuterated solvent into contact with hydrogen gas under pressure in the coexistence with a catalyst selected from a palladium catalyst, a platinum catalyst, a nickel catalyst, a cobalt catalyst, an iridium catalyst, and a rhodium catalyst and a ruthenium catalyst which are not coordinated with a ligand, and (2) a catalytic deuteration method of a compound having a reducible functional group, comprising bringing the heavy hydrogen gas obtained by the above (1) into contact with the compound having a reducible functional group in the coexistence with a catalytic reduction catalyst.Type: ApplicationFiled: January 16, 2006Publication date: June 19, 2008Applicant: WAKO PURE CHEMICAL INDUSSRIES, LTD.Inventors: Kosaku Hirota, Hironao Sajiki, Nobuhiro Ito
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Publication number: 20080071107Abstract: The object of the present invention is to provide a method for efficiently and industrially deuterating a haloacrylic acid or salt thereof.Type: ApplicationFiled: June 20, 2005Publication date: March 20, 2008Applicant: WAKO PURE CHEMICAL INDUSTRIES, LTDInventors: Tsuneaki Maesawa, Nobuhiro Ito, Kosaku Hirota, Hironao Sajiki
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Publication number: 20080045724Abstract: The object of the present invention is to provide a polyimide compound useful as a raw material of a polymer for an optical waveguide that has excellent transparency and heat resistance, low moisture absorption, a small optical transmission loss, a high refractive index and good adhesion to a base material or a substrate.Type: ApplicationFiled: May 17, 2005Publication date: February 21, 2008Applicant: WAKO PURE CHEMICAL INDUSTRIES, LTD.Inventors: Kazushige Muto, Tsuneaki Maesawa, Nobuhiro Ito, Tsutomu Watahiki, Kosaku Hirota, Hironao Sajiki
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Publication number: 20070255076Abstract: The present invention relates to a method for deuteration of a compound having an aromatic ring, using an activated catalyst, and the method comprises reacting a compound having an aromatic ring with heavy hydrogen source in the presence of an activated catalyst selected from a platinum catalyst, a rhodium catalyst, a ruthenium catalyst, a nickel catalyst and a cobalt catalyst.Type: ApplicationFiled: July 10, 2003Publication date: November 1, 2007Applicant: Wako Pure Chemical Industries, Ltd.Inventors: Nobuhiro Ito, Tsuneaki Maesawa, Kazushige Muto, Kosaku Hirota, Hironao Sajiki
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Publication number: 20070155617Abstract: A functional group-selective hydrogenation catalyst is provided, which is capable of selectively hydrogenating an aliphatic carbon-carbon double bond, aliphatic carbon-carbon triple bond, aromatic formyl group or aromatic nitro group contained in an organic compound. The catalyst includes a carrier, and palladium and an organic sulfur compound supported jointly thereon.Type: ApplicationFiled: December 1, 2006Publication date: July 5, 2007Applicant: N. E. CHEMCAT CORPORATIONInventors: Hironao SAJIKI, Tomohiro Maegawa, Kosaku Hirota
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Patent number: 7126023Abstract: The present invention relates to a method for deuteration of an inert alkane using activated palladium carbon. The present invention discloses “A method for deuteration of a hydrogen atom of a methyl group or a hydrogen atom bonded to a carbon atom at benzyl position and the other carbon atoms of an alkylene group having not less than 2 carbon atoms, in a compound containing the methyl group or the-alkylene group having not less than 2 carbon atoms, directly bonded to an aromatic ring which may have a substituent, which comprises placing said compound in a deuterated solvent in the presence of activated palladium carbon, under sealed reflux condition”.Type: GrantFiled: November 12, 2002Date of Patent: October 24, 2006Assignee: Wako Pure Chemical Industries, Ltd.Inventors: Kosaku Hirota, Hironao Sajiki
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Publication number: 20060116535Abstract: The present invention relates to a method for deuteration of a compound represented by the general formula [1]: R1—X—R2??[1] wherein, R1 represents an alkyl group or an aralkyl group, which may have a carbon-carbon double bond and/or triple bond; R2 represents an alkyl group which may have a carbon-carbon double bond and/or triple bond, an aryl group, an aralkyl group, an alkoxy group, an aryloxy group or a hydroxyl group; X represents a carbonyl group or a hydroxylmethylene group, R1 and R2 may form an alicyclic ring together with a carbon atom contained in X; provided that R2 represents an alkyl group which may have a carbon-carbon double bond and/or triple bond, an aryl group or an aralkyl group when X is a hydroxylmethylene group, comprising reacting the compound represented by the general formula [1] with a heavy hydrogen source in the co-presence of an activated catalyst selected from a palladium catalyst, a platinum catalyst, a rhodium catalyst, a ruthenium catalyst, a nickel catalyst and a cobaltType: ApplicationFiled: November 7, 2003Publication date: June 1, 2006Applicant: Wako Pure Chemical Industries, Ltd.Inventors: Nobuhiro Ito, Tsuneaki Maesawa, Kazushige Muto, Kosaku Hirota, Kosaku Hirota, Hironao Sajiki
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Publication number: 20060025596Abstract: The present invention relates to a method for deuteration of a heterocyclic ring, which comprises subjecting a compound having a heterocyclic ring to sealed refluxing state in a deuterated solvent in the presence of an activated catalyst selected form a palladium catalyst, a platinum catalyst, a rhodium catalyst, a ruthenium catalyst, a nickel catalyst and a cobalt catalyst. In accordance with a method of the present invention, a hydrogen atom belonging to a heterocyclic ring of a compound having a heterocyclic ring can be very efficiently deuterated because temperature of deuteration reaction can be maintained at higher than boiling point of the solvent. Further, a method for deuteration of the present invention can be applied widely to deuteration of various compounds having a heterocyclic ring which are liable to decomposition under supercritical conditions or acidic conditions, leading to industrial and efficient deuteration of a compound having a heterocyclic ring.Type: ApplicationFiled: November 7, 2003Publication date: February 2, 2006Inventors: Nobuhiro Ito, Tsuneaki Maesawa, Kazushige Muto, Kosaku Hirota, Hironao Sajiki
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Publication number: 20050177015Abstract: The present invention relates to a method for deuteration of an inert alkane using activated palladium carbon. The present invention discloses “A method for deuteration of a hydrogen atom of a methyl group or a hydrogen atom bonded to a carbon atom at benzyl position and the other carbon atoms of an alkylene group having not less than 2 carbon atoms, in a compound containing the methyl group or the-alkylene group having not less than 2 carbon atoms, directly bonded to an aromatic ring which may have a substituent, which comprises placing said compound in a deuterated solvent in the presence of activated palladium carbon, under sealed reflux condition”.Type: ApplicationFiled: November 12, 2002Publication date: August 11, 2005Applicant: WAKO PURE CHEMICAL INDUSTRIES LTDInventors: Kosaku Hirota, Hironao Sajiki
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Patent number: 4171429Abstract: There is provided a novel process for pyrimidine to pyrimidine transformations by the displacement of the 1,2,3-portion of a pyrimidine by a 1,3-ambident nucleophile. The novel process requires that the 1 and 3 nitrogens of the pyrimidine moiety be substituted. The novel process makes available, inter alia, novel uracils, simple methods of radioisotopically labeling pyrimidine nuclei, a simple and inexpensive method of preparing the important antiviral and antileukemic material pseudoisocytidine and its new active analog 2'-deoxypseudoisocytidine.Type: GrantFiled: March 29, 1977Date of Patent: October 16, 1979Assignee: Research CorporationInventors: Kyoichi A. Watanabe, Kosaku Hirota, Chung K. Chu, Uri Reichman, Jack J. Fox