Patents by Inventor Claus Dittel

Claus Dittel 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).

  • Publication number: 20070112206
    Abstract: A process for the manufacture of 3-phytyl-2,5,6-trimethylhydroquinone-1-acetate, and optionally therefrom tocopheryl acetate, comprises either C-alkylating 2,3,6-trimethylhydroquinone-1-acetate with isophytol or phytol in the presence of a sulphur(VI) containing catalyst of the formula R1SO2OH, wherein R1 signifies hydroxy, halogen, lower alkyl, halogenated lower alkyl or aryl, in an aprotic organic solvent, or O-alkylating 2,3,6-trimethylhydroquinone-1-acetate with a phytyl halide in a polar aprotic organic solvent in the presence of a base, and subjecting the so-obtained 4-O-phytyl-2,3,6-trimethylhydro-quinone-1-acetate to a rearrangement reaction, and in each case optionally submitting the so-obtained 3-phytyl-2,5,6-trimethylhydroquinone-1-acetate to a ring closure reaction to produce tocopheryl acetate.
    Type: Application
    Filed: December 13, 2006
    Publication date: May 17, 2007
    Inventors: Werner Bonrath, Claus Dittel, Thomas Netscher, Thomas Pabst, Rudolf Schmid
  • Patent number: 7169943
    Abstract: A process for the manufacture of 3-phytyl-2,5,6-trimethylhydroquinone-1-acetate, and optionally therefrom tocopheryl acetate, comprises either C-alkylating 2,3,6-trimethylhydroquinone-1-acetate with isophytol or phytol in the presence of a sulphur(VI) containing catalyst of the formula R1SO2OH, wherein R1 signifies hydroxy, halogen, lower alkyl, halogenated lower alkyl or aryl, in an aprotic organic solvent, or O-alkylating 2,3,6-trimethylhydroquinone-1-acetate with a phytyl halide in a polar aprotic organic solvent in the presence of a base, and subjecting the so-obtained 4-O-phytyl-2,3,6-trimethylhydroquinone-1-acetate to a rearrangement reaction, and in each case optionally submitting the so-obtained 3-phytyl-2,5,6-trimethylhydroquinone-1-acetate to a ring closure reaction to produce tocopheryl acetate.
    Type: Grant
    Filed: September 29, 2003
    Date of Patent: January 30, 2007
    Assignee: DSM IP Assets B.V.
    Inventors: Werner Bonrath, Claus Dittel, Thomas Netscher, Thomas Pabst, Rudolf Schmid
  • Patent number: 7135580
    Abstract: The present invention is concerned with a novel process for the manufacture of ?-tocopheryl acetate which comprises reacting 2,3,6-trimethylhydroquinone-1-acetate with a compound selected from the group consisting of phytol (formula IV with R?OH), iso-phytol (formula III with R?OH), and (iso) phytol derivatives represented by the following formulae III and IV with R?C2-to C5-alkonoyloxy, benzoyloxy, mesyloxy, bezenesul-fonyloxy or tosyloxy, (IV) in the presence of a catalyst of the formula Mn+(R1SO3?)n, wherein Mn+ is a silver, copper, gallium, hafnium or rare earth metal cation, n is the valence of the cation Mn+, and R1 is fluorine, C1-8-perfluoroalkyl or perfluoroaryl, and, if required, cyclizing any 3-phytyl-2,5,6-trimethylhydroquinone-1-acetate or a double bond isomer thereof obtained as an intermediate reaction product, to produce ?-tocopheryl acetate. In the catalyst Mn+ is preferably Ag+, Cu+, Ga3+, Sc3+, Lu3+, Ho3+, Tm3+, Yb3+ or Hf4+.
    Type: Grant
    Filed: December 22, 2003
    Date of Patent: November 14, 2006
    Assignee: DSM IP Assets B.V.
    Inventors: Werner Bonrath, Claus Dittel, Lisa Giraudi, Thomas Netscher, Thomas Pabst
  • Publication number: 20060094886
    Abstract: A process for the manufacture of 3-phytyl-2,5,6-trimethylhydroquinone-1-acetate, and optionally therefrom tocopheryl acetate, comprises either C-alkylating 2,3,6-trimethylhydroquinone-1-acetate with isophytol or phytol in the presence of a sulphur(VI) containing catalyst of the formula R1SO2OH, wherein R1 signifies hydroxy, halogen, lower alkyl, halogenated lower alkyl or aryl, in an aprotic organic solvent, or O-alkylating 2,3,6-trimethylhydroquinone-1-acetate with a phytyl halide in a polar aprotic organic solvent in the presence of a base, and subjecting the so-obtained 4-O-phytyl-2,3,6-trimethylhydroquinone-1-acetate to a rearrangement reaction, and in each case optionally submitting the so-obtained 3-phytyl-2,5,6-trimethylhydroquinone-1-acetate to a ring closure reaction to produce tocopheryl acetate.
    Type: Application
    Filed: September 29, 2003
    Publication date: May 4, 2006
    Inventors: Werner Bonrath, Claus Dittel, Thomas Netscher, Thomas Pabst, Rudolf Schmid
  • Publication number: 20060052618
    Abstract: The present invention is concerned with a novel process for the manufacture of ?-tocopheryl acetate which comprises reacting 2,3,6-trimethylhydroquinone-1-acetate with a compound selected from the group consisting of phytol (formula IV with R?OH), iso-phytol (formula III with R?OH), and (iso) phytol derivatives represented by the following formulae III and IV with R?C2-to C5-alkonoyloxy, benzoyloxy, mesyloxy, bezenesul-fonyloxy or tosyloxy, (IV) in the presence of a catalyst of the formula Mn+(R1SO3?)n, wherein Mn+ is a silver, copper, gallium, hafnium or rare earth metal cation, n is the valence of the cation Mn+, and R1 is fluorine, C1-8-perfluoroalkyl or perfluoroaryl, and, if required, cyclizing any 3-phytyl-2,5,6-trimethylhydroquinone-1-acetate or a double bond isomer thereof obtained as an intermediate reaction product, to produce ?-tocopheryl acetate. In the catalyst Mn+ is preferably Ag+, Cu+, Ga3+, Sc3+, Lu3+, Ho3+, Tm3+, Yb3+ or Hf4+.
    Type: Application
    Filed: December 22, 2003
    Publication date: March 9, 2006
    Inventors: Werner Bonrath, Claus Dittel, Lisa Giraudi, Thomas Netscher, Thomas Pabst