Patents by Inventor Gunther Helmchen

Gunther Helmchen 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).

  • Optically active diphosphine ligands
    Patent number: 5990320
    Abstract: Optically active diphosphine ligands of the formula I, ##STR1## where: R.sup.1 is hydrogen, C.sub.1 -C.sub.10 -acyl, C.sub.1 -C.sub.10 -alkyl, C.sub.2 -C.sub.10 -alkenyl, each of which may be linear or branched, aryl, arylalkyl, in which the ring systems may be substituted in each case, ##STR2## R.sup.2, R.sup.3 independently of one another are C.sub.1 -C.sub.10 -alkyl, which may be linear or branched, aryl, arylalkyl, in which the ring systems may be substituted in each case,R.sup.4, R.sup.5, R.sup.6 independently of one another are C.sub.1 -C.sub.10 -alkyl, which may be linear or branched, aryl, arylalkyl, in which the ring systems may be substituted in each case.
    Type: Grant
    Filed: June 16, 1998
    Date of Patent: November 23, 1999
    Assignee: BASF Aktiengesellschaft
    Inventors: Gunther Helmchen, Christoph Murmann
  • Ruthenium complexes with a chiral, bidentate phosphine/oxazoline ligand for enantioselective transfer hydrogenation of prochiral ketones
    Patent number: 5693820
    Abstract: Ruthenium complexes with a chiral ligand of the general formula: ##STR1## are used for the enantioselective transfer hydrogenation of prochiral ketones.
    Type: Grant
    Filed: December 20, 1996
    Date of Patent: December 2, 1997
    Assignee: BASF Aktiengesellschaft
    Inventors: Gunther Helmchen, Thomas Langer