Patents by Inventor Hans Wolfram

Hans Wolfram 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 ring-chlorinating toluene
    Patent number: 4647709
    Abstract: In the ring chlorination of toluene, a particularly high proportion of p-chlorotoluene is obtained by using in addition to the customary Lewis acid catalysts as cocatalyst a chlorination product of 2,8-dimethylphenoxathiin which comprises in the main 1,3,7,9-tetrachloro-2,8-dimethylphenoxathiin of the formula ##STR1##
    Type: Grant
    Filed: August 29, 1985
    Date of Patent: March 3, 1987
    Assignee: Hoechst Aktiengesellschaft
    Inventor: Hans Wolfram
  • Process for the manufacture of 1,3,5-trichlorobenzene
    Patent number: 4306103
    Abstract: 1,3,5-trichlorobenzene is manufactured by treating 5-chloro-1,3-dinitrobenzene and/or 3,5-dichloronitrobenzene with chlorine, at a temperature from about 200.degree. to 270.degree. C., preferably from about 230.degree. to 250.degree. C. The resulting process product is an intermediate, for example in plant protection.
    Type: Grant
    Filed: May 16, 1980
    Date of Patent: December 15, 1981
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Gert Volkwein, Konrad Baessler, Hans Wolfram