Patents by Inventor Kazutoshi Takatsuna

Kazutoshi Takatsuna 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).

  • Patent number: 5145979
    Abstract: There are provided processes for the preparation of .gamma.-methacryloxypropylsilane compounds which comprise carrying out the reaction of allyl methacrylate with a hydrosilane compound in the presence of a platinum catalyst, while allowing at least one of a hindered phenol compound and an aromatic amine compound to coexist in the reaction system with an alkylamine compound or an amide compound, or with a gas containing molecular oxygen, or with a phenol compound having an aminoalkylene group. By using these processes as provided, gelation of the reaction mixture in the reaction system and during the course of purification thereof by distillation can effectively be avoided, and the desired .gamma.-methacryloxypropylsilane compounds can be obtained in good yield.
    Type: Grant
    Filed: August 22, 1991
    Date of Patent: September 8, 1992
    Assignee: Tonen Corporation
    Inventors: Kazutoshi Takatsuna, Masaaki Ishii, Hideaki Ogawa, Akihito Shinohara, Kouji Shiozawa, Yoshiharu Okumura, Masako Ishikawa
  • Patent number: 4927953
    Abstract: A process for preparing aminopropyl silanes comprises reacting an allylamine with a hydrosilane in the presence of a ruthenium compound having at least one tertiary phosphine ligand as a catalyst. By the proposed process the corresponding gamma-aminopropyl silane can be prepared in a high yield in a short period of reaction time.
    Type: Grant
    Filed: September 11, 1989
    Date of Patent: May 22, 1990
    Assignee: Tonen Corporation
    Inventors: Kazutoshi Takatsuna, Kouji Shiozawa, Yoshiharu Okumura
  • Patent number: 4921988
    Abstract: A process for preparing aminopropyl silanes in which an allylamine is reacted with a hydrosilane in the presence of a catalyst comprising (i) metallic rhodium or a rhodium compound and (ii) a basic compound. By the proposed process the corresponding gammaaminopropyl silane can be prepared in a high selectivity and yield within a short period of reaction time.
    Type: Grant
    Filed: December 6, 1988
    Date of Patent: May 1, 1990
    Assignee: Toa Nenryo Kogyo Kabushiki Kaisha
    Inventors: Kazutoshi Takatsuna, Mamoru Tachikawa, Kouji Shinozawa, Masashi Nakajima, Akihito Shinohara, Yoshiharu Okumura
  • Patent number: 4897501
    Abstract: In a process for preparing aminopropyl alkoxy silanes comprising reacting an allylamine with a hydro-alkoxy silane in the presence of a rhodium catalyst, the improvement which comprises use of a rhodium phosphide or its oligomer as said rhodium catalyst. By this process the desired gamma-isomer can be prepared in a high selectivity and yield within a short reaction time.
    Type: Grant
    Filed: July 29, 1988
    Date of Patent: January 30, 1990
    Assignee: Toa Nenryo Kogyo Kabushiki Kaisha
    Inventors: Kazutoshi Takatsuna, Mamoru Tachikawa, Kouji Shiozawa, Nobukazu Okamoto, Yoshiharu Okumura
  • Patent number: 4888436
    Abstract: A process for preparing aminopropyl alkoxy silanes comprising reacting an allylamine having at least one active hydrogen atom attached to the amine nitrogen atom with a hydro-alkoxy silane having from 1 to 3 alkoxy groups attached to the silicon atom in the presence of a rhodium complex having inorganic ligands, at least one of said ligands being carbonyl. By this process the desired gamma-isomer can be prepared in a high selectivity and yield within a short reaction time. When the reaction is carried out in the presence of carbon monoxide and/or a cyclic olefinic compound, the selectivity and yield of the gamma-isomer can be further improved. The presence of carbon monooxide in the reaction system further serves to lengthen the catalyst life and to reduce the amount of the catalyst to be used.
    Type: Grant
    Filed: March 28, 1988
    Date of Patent: December 19, 1989
    Assignee: Toa Nenryo Kogyo Kabushiki Kaisha
    Inventors: Kouji Shiozawa, Haruko Takai, Kazutoshi Takatsuna, Nobukazu Okamoto, Yoshiharu Okumura, Chihiro Imai
  • Patent number: 4775651
    Abstract: Silanes are produced by the disproportionation and/or redistribution reaction of chlorosilanes using a novel catalyst having a longer life and consisting of a quaternary phosphonium salt bonded to an organic macromolecule or polymer, represented by the following general formula: ##STR1## wherein .circle.P.circle. is an organic macromolecule or polymer, A is a bridging group between phosphorus and the organic macromolecule or polymer, R.sup.1, R.sup.2 and R.sup.3 are selected from the group consisting of hydrogen, C.sub.1 -C.sub.20 alkyl groups and aralkyl groups such as benzyl and phenethyl groups, which can contain oxygen or halogen atoms, and X is a halogen atom.
    Type: Grant
    Filed: November 17, 1987
    Date of Patent: October 4, 1988
    Assignee: Toa Nenryo Kogyo Kabushiki Kaisha
    Inventors: Mamoru Tachikawa, Kazutoshi Takatsuna, Kouji Shiozawa, Yoshiharu Okumura, Takeo Koyama
  • Patent number: 4725420
    Abstract: Silanes are produced by the disproportionation and/or redistribution reaction of chlorosilanes using a novel catalyst having a longer life and consisting of a quaternary phosphonium salt bonded to an organic macromolecule or polymer, represented by the following general formula: ##STR1## wherein .circle.P is an organic macromolecule or polymer, A is a bridging group between phosphorus and the organic macromolecule or polymer, R.sup.1, R.sup.2 and R.sup.3 are selected from the group consisting of hydrogen, C.sub.1 -C.sub.20 alkyl groups and aralkyl groups such as benzyl and phenethyl groups, which can contain oxygen or halogen atoms, and X is a halogen atom.
    Type: Grant
    Filed: September 19, 1986
    Date of Patent: February 16, 1988
    Assignee: Toa Nenryo Kogyo Kabushiki Kaisha
    Inventors: Mamoru Tachikawa, Kazutoshi Takatsuna, Kouji Shiozawa, Yoshiharu Okumura, Takeo Koyama