Patents by Inventor Ernst Ingo Leupold

Ernst Ingo Leupold 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 preparing alkanephosphonic anhydrides
    Patent number: 5710330
    Abstract: Process for preparing alkanephosphonic anhydrides of the formula (I) ##STR1## where R is straight-chain or branched unsubstituted C.sub.1 -C.sub.6 -alkyl and n.gtoreq.3, which comprises pyrolytically eliminating water from an alkanephosphonic acid of the formula (II) or a pyroalkanephosphonic acid of the formula (III) ##STR2## where R is straight-chain or branched C.sub.1 -C.sub.6 -alkyl, without addition of solvent and removing the water from the reaction mixture by means of an inert gas stream.
    Type: Grant
    Filed: November 2, 1995
    Date of Patent: January 20, 1998
    Assignee: Hoechst AG
    Inventors: Carl Christoph Mollenkopf, Ernst Ingo Leupold, Gunter Roscher
  • Dimerization of cyclohexylidene-acetonitrile and hydrogenation of the resulting substituted glutaric acid dinitrile
    Patent number: 4009209
    Abstract: A process is provided for the dimerization of cyclohexylidene-acetonitrile to form 2-(1-cyclohexenyl)-3,3-pentamethylene-glutaric acid dinitrile and the hydrogenation thereof to form 1,5-diamino-2-(1-cyclohexenyl)-3,3-pentamethylene-pentane.
    Type: Grant
    Filed: February 9, 1976
    Date of Patent: February 22, 1977
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Ernst Ingo Leupold, Hans-Jurgen Arpe