Patents by Inventor Robert U. Osterwalder

Robert U. Osterwalder 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 for the preparation of 5-nitro-1,4-naphthoquinone
    Patent number: 4880571
    Abstract: A process for the preparation of 5-nitro-1,4-naphthoquinones of formula ##STR1## wherein R is hydrogen, a C.sub.1 -C.sub.4 alkyl radical or a C.sub.1 -C.sub.4 alkoxy radical, by oxidation of 1-nitronaphthalene or a suitably substituted 1-nitronaphthalene, which process comprises carrying out the reaction with manganese(III) sulfate as oxidizing agent or a mixture of manganese(III) sulfate and cerium sulfate.The maganese(III) sulfate consumed can be regenerated electrolytically with good current yield. The process is environmentally safe, as the oxidizing agent and the solvent, if any, can be reused.
    Type: Grant
    Filed: October 22, 1986
    Date of Patent: November 14, 1989
    Assignee: Ciba-Geigy Corporation
    Inventors: Christos Comninellis, Robert U. Osterwalder, Eric Plattner, Gottfried Seifert