Patents by Inventor Takahiro Kotera

Takahiro Kotera 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).

  • Process of producing 2-cyano-4-oxo-4H-benzopyran compounds
    Patent number: 5659051
    Abstract: There is disclosed a process of producing a 2-cyano-4-oxo-4H-benzopyran compound of the general formula (2): ##STR1## wherein R.sup.1 and R.sup.2 are independently hydrogen, halogen, hydroxy, C.sub.1 -C.sub.5 alkyl, C.sub.1 -C.sub.5 alkoxy, nitro or a group of the RCONH wherein R is C.sub.1 -C.sub.20 alkyl, phenyl, phenyl-substituted (C.sub.1 -C.sub.20) alkyl, phenyl (C.sub.1 -C.sub.20)alkoxyphenyl or (C.sub.1 -C.sub.20) alkoxyphenyl. This production process is characterized in that a carboxamide of the general formula (1): ##STR2## wherein R.sup.1 and R.sup.2 are each as defined above, is reacted with a dehydrating agent in the presence of a pyridine compound of the general formula (4): ##STR3## wherein A.sup.1 and A.sup.2 are independently hydrogen or C.sub.1 -C.sub.5 alkyl.
    Type: Grant
    Filed: July 11, 1994
    Date of Patent: August 19, 1997
    Assignee: Sumitomo Chemical Company, Limited
    Inventors: Takayuki Higashii, Hideki Ushio, Yukari Fujimoto, Tsutomu Matsumoto, Masayoshi Minai, Katsuichi Yasunaga, Hiroshi Sogabe, Takahiro Kotera