Patents by Inventor Tetsuhiko Watanabe

Tetsuhiko Watanabe 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).

  • Method for preparing 4-substituted-N-methylbenzothiazolone derivatives
    Patent number: 4293702
    Abstract: A process for producing N-alkylbenzothiazolone derivatives of the formula (I), ##STR1## wherein R.sub.1 is a hydrogen, chlorine, bromine, fluorine atom or a methyl group, and R.sub.2 is an alkyl group having 1 to 5 carbon atoms, from 2-halogenobenzothiazole derivatives of the formula (II), ##STR2## wherein R.sub.1 is as defined above and X is a chlorine, bromine or fluorine atom, which is a starting material, through the intermediate of 2-alkoxybenzothiazole derivatives of the formula (III), ##STR3## wherein R.sub.1 and R.sub.2 are as defined above, or benzothiazolone derivatives of the formula (IV), ##STR4## wherein R.sub.1 is as defined above.
    Type: Grant
    Filed: June 18, 1979
    Date of Patent: October 6, 1981
    Assignee: Sumitomo Chemical Company, Limited
    Inventors: Takeaki Umemura, Haruki Morino, Tetsuhiko Watanabe, Tamon Uematsu
  • Method for preparing 3-methyl-2-(4-halogenophenyl)-butyronitrile
    Patent number: 4012428
    Abstract: A method for preparing a 3-methyl-2-(4'-halogenophenyl)-butyronitrile which comprises alkylating a p-halogenophenylacetonitrile by reacting the p-halogenophenylacetonitrile with an isopropyl halide in the presence of an aqueous alkali metal hydroxide solution, using an organic guaternary ammonium salt as a catalyst.
    Type: Grant
    Filed: November 26, 1975
    Date of Patent: March 15, 1977
    Assignee: Sumitomo Chemical Company, Limited
    Inventors: Nobuo Ohno, Takeaki Umemura, Tetsuhiko Watanabe