Patents by Inventor Hans-Jurgen Leitung

Hans-Jurgen Leitung 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: 6930216
    Abstract: A method for the nuclear chlorination of ortho-xylene using a chlorinating agent in the presence of at least one Friedel-Crafts catalyst and chloro-substituted 2,8-dimethylphenoxathiin as co-catalyst.
    Type: Grant
    Filed: September 10, 2003
    Date of Patent: August 16, 2005
    Assignee: Clariant GmbH
    Inventors: Karl-Ernst Mack, Hans-Jürgen Leitung, Daniel Decker
  • Publication number: 20040054239
    Abstract: A method for the nuclear chlorination of ortho-xylene using a chlorinating agent in the presence of at least one Friedel-Crafts catalyst and chloro-substituted 2,8-dimethylphenoxathiin as co-catalyst.
    Type: Application
    Filed: September 10, 2003
    Publication date: March 18, 2004
    Applicant: Clariant GmbH
    Inventors: Karl-Ernst Mack, Hans-Jurgen Leitung, Daniel Decker
  • Patent number: 6242646
    Abstract: The present invention relates to a process for preparing 2,4-dichloro-5-hydroxyacetanilide by reacting 3-hydroxyacetanilide with sulfuryl chloride in the presence of from 3 to 30 parts by weight of an aliphatic carboxylic acid having from 1 to 6 carbon atoms per part by weight of 3-hydroxyacetanilide with vigorous mixing at from 20 to 100° , removing gaseous components from the reaction mixture, setting a ratio of from 1.0 to 6 parts by weight of aliphatic carboxylic acid per part by weight of 3-hydroxyacetanilide employed and removing 2,4-dichloro-5-hydroxyacetanilide as a solid.
    Type: Grant
    Filed: September 27, 2000
    Date of Patent: June 5, 2001
    Assignee: Clariant GmbH
    Inventors: Frank Sistig, Hans-Jürgen Leitung, Stefan Krause