Patents by Inventor Fritz W. Lange

Fritz W. Lange 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).

  • Novel process for the preparation of N,N'-bisacyl hydrazides
    Patent number: 4357277
    Abstract: An improved process for the preparation of acyl hydrazides of the formula ##STR1## wherein A and B individually are a group of the formula ##STR2## wherein R.sub.1 is selected from the group consisting of hydrogen and alkyl of 1 to 4 carbon atoms, x is 0 or 1 and R.sub.2 and R.sub.3 are individually selected from the group consisting of hydrogen and alkyl of 1 to 4 carbon atoms and n and m are individually 0, 1, 2 or 3 by reacting a compound of the formula ##STR3## with a hydrazide of the formula ##STR4## the improvement comprising effecting the reaction in the presence of at least one catalyst selected from the group consisting of amines, amine alkoxides and quaternary ammonium hydroxides.
    Type: Grant
    Filed: January 12, 1981
    Date of Patent: November 2, 1982
    Assignee: Rutgerswerke Aktiengesellschaft
    Inventors: Winfried Orth, Fritz W. Lange, Werner Fickert
  • Process for the preparation of bisacyl hydrazines
    Patent number: 4332728
    Abstract: An improved process for the preparation of acyl hydrazides of the formula ##STR1## wherein A and B individually are a group of the formula ##STR2## wherein R.sub.1 is selected from the group consisting of hydrogen and alkyl of 1 to 4 carbon atoms, x is 0 or 1 and R.sub.2 and R.sub.3 are individually selected from the group consisting of hydrogen and alkyl of 1 to 4 carbon atoms and n and m are individually 0, 1,2 or 3 by reacting a compound of the formula ##STR3## with a hydrazide of the formula ##STR4## the improvement comprising effecting the reaction in the presence of at least one catalyst of the formula R'--OMe wherein R' is selected from the group consisting of hydrogen and alkyl of 1 to 4 carbon atoms and Me is an alkali metal.
    Type: Grant
    Filed: January 12, 1981
    Date of Patent: June 1, 1982
    Assignee: Rutgerswerke Aktiengesellschaft
    Inventors: Winfried Orth, Fritz W. Lange, Werner Fickert