Patents by Inventor Francois Frisou

Francois Frisou 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).

  • Preparation of O-alkyl, S,S-dialkylphosphorodithioates
    Patent number: 4950784
    Abstract: The O-alkyl S,S-dialkylphosphorodithioates, e.g., ethoprophos, are facilely prepared, in improved yields and having great purity, by reacting an alkylphosphate dihalogenide, e.g., a dichloride, with a 1.5 to 8 mol excess of a thiol, in the presence of a 0.1 to 5 mol excess of an acid acceptor, with both molar excesses being per mole of said dihalogenide.
    Type: Grant
    Filed: July 24, 1987
    Date of Patent: August 21, 1990
    Assignee: Rhone-Poulenc Agrochimie
    Inventors: Jean-Michel Brochard, Francois Frisou, Pierre Le Roy