Patents by Inventor Daniel A. Dobbs

Daniel A. Dobbs 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).

  • Ruthenium catalysts and method for making same
    Patent number: 6455460
    Abstract: A catalyst of ruthenium (II) comprising bidentate phosphine ligands is described which is obtained by a process that comprises treating equimolar amounts of an appropriate Ru complex and a bidentate diphosphine ligand with an acid of the formula H-Anion, wherein the anion is a non-coordinating anion, said acid being used in a ratio of 1 molar equivalent per mole of Ru complex and the treatment being carried out in a non-coordinating or weakly coordinating medium, under an oxygen-free atmosphere. Said catalyst is useful for the preparation of the preferred isomer of the Hedione®, having the configuration (+)-(1R)-cis, and of many other substrates comprising highly hindered carbon-carbon double bonds.
    Type: Grant
    Filed: October 18, 2000
    Date of Patent: September 24, 2002
    Assignee: Firmenich SA
    Inventors: Daniel A. Dobbs, Koenraad P. M. Vanhessche, Valentin Rautenstrauch
  • Ruthenium catalysts and their use in the asymmetric hydrogenation of weakly coordinating substrates
    Patent number: 6214763
    Abstract: A catalyst of Ru comprising bidentate phosphine ligands is described which is obtained by a process that comprises treating equimolar amounts of an appropriate Ru complex and a bidentate diphosphine ligand with an acid of the formula H-Anion, wherein the anion is a non-coordinating anion, said acid being used in a ratio of 1 molar equivalent per mole of Ru complex and the treatment being carried out in a non-coordinating or weakly coordinating medium, under an oxygen-free atmosphere. Said catalyst is useful for the preparation of the preferred isomer of the Hedione®, having the configuration (+)-(1R)-cis, and of many other substrates comprising highly hindered carbon-carbon double bonds.
    Type: Grant
    Filed: May 19, 1998
    Date of Patent: April 10, 2001
    Assignee: Firmenich SA
    Inventors: Daniel A. Dobbs, Koenraad P. M. Vanhessche, Valentin Rautens Trauch