Patents by Inventor Donald Valentine, Jr.

Donald Valentine, Jr. 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 making alkyl arsine compounds
    Patent number: 5003093
    Abstract: Alkyl arsines are made by reaction of arsine and an olefin in contact with acid catalyst. Products are mono and di-substituted arsines, e.g. alkyl and dialkyl arsines. The products contain practically no metallic or oxygenating impurities.
    Type: Grant
    Filed: June 19, 1989
    Date of Patent: March 26, 1991
    Assignee: American Cyanamid
    Inventor: Donald Valentine, Jr.
  • Metalorganic vapor phase epitaxial growth of group II-VI semiconductor materials
    Patent number: 4920068
    Abstract: A process to produce one or more Group II-VI epitazial layers over a crystalline substrate by directing flows of one or more Group II components and a Group VI metalorganic vapor to a heated substrate whereby the vapors thereby react to form the epitaxial layer(s), is improved in terms of lower reaction temperatures and higher product quality if, as the Group VI metalorganic vapor source, there is used a tellurium compound of the formula: ##STR1## wherein R.sup.1 and R.sup.2 are, independently, hydrogen or C.sub.1 -C.sub.4 alkyl, preferably, hydrogen.
    Type: Grant
    Filed: April 2, 1986
    Date of Patent: April 24, 1990
    Assignee: American Cyanamid Company
    Inventors: Donald Valentine, Jr., Duncan W. Brown
  • Process for making alkyl arsine compounds
    Patent number: 4857655
    Abstract: Alkyl arsines are made by reaction of arsine and an olefin in contact with acid catalyst. Products are mono and di-substituted arsines, e.g. alkyl and di-alkyl arsines. The products contain practically no metallic or oxygenating impurities.
    Type: Grant
    Filed: January 20, 1988
    Date of Patent: August 15, 1989
    Assignee: American Cyanamid Company
    Inventor: Donald Valentine, Jr.
  • Chiral phosphines
    Patent number: 4343741
    Abstract: Novel substituted diphenyl tertiary phosphines of a pyrrolidine carboxylic acid derivative and their use as catalysts in the enantioselective hydrogenation of .alpha.-keto-.beta.,.beta.-dimethyl-.gamma.-butyrolactone.
    Type: Grant
    Filed: April 22, 1981
    Date of Patent: August 10, 1982
    Assignee: Hoffmann-La Roche Inc.
    Inventors: John M. Townsend, Donald Valentine, Jr.
  • Pyrroles and pyrrolidines
    Patent number: 4316847
    Abstract: The preparation of racemic and optically pure tryptophans is described. The D-enantiomers of the 6-substituted compounds possess a potent sweetening capability. Novel intermediates are also disclosed.
    Type: Grant
    Filed: October 22, 1980
    Date of Patent: February 23, 1982
    Assignee: Hoffmann-La Roche Inc.
    Inventors: Andrew D. Batcho, Urs O. Hengartner, Willy Leimgruber, John W. Scott, Donald Valentine, Jr.
  • Novel syntheses of tryptophans
    Patent number: 4256641
    Abstract: The preparation of racemic and optically pure tryptophans is described. The D-enantiomers of the 6-substituted compounds possess a potent sweetening capability. Novel intermediates are also disclosed.
    Type: Grant
    Filed: July 30, 1979
    Date of Patent: March 17, 1981
    Assignee: Hoffmann-La Roche Inc.
    Inventors: Andrew D. Batcho, Urs O. Hengartner, Willy Leimgruber, John W. Scott, Donald Valentine, Jr.
  • Lower alkyl esters of .alpha.-formamido,.alpha.-carbalkoxy tryptophans
    Patent number: 4140697
    Abstract: Lower alkyl esters of 2-formamido-3(4,5,6 or 7-methyl substituted-3-indolyl)-2-carbalkoxy propionic acid which are useful as intermediates for tryptophane sweetners.
    Type: Grant
    Filed: November 9, 1977
    Date of Patent: February 20, 1979
    Assignee: Hoffmann-La Roche Inc.
    Inventors: Andrew D. Batcho, Urs O. Hengartner, Willy Leimgruber, John W. Scott, Donald Valentine, Jr.
  • Synthesis of tryptophans
    Patent number: 4073795
    Abstract: The preparation of racemic and optically pure tryptophans is described. The D-enantiomers of the 6-substituted compounds possess a potent sweetening capability. Novel intermediates are also disclosed.
    Type: Grant
    Filed: June 22, 1976
    Date of Patent: February 14, 1978
    Assignee: Hoffmann-La Roche Inc.
    Inventors: Andrew David Batcho, Urs Oskar Hengartner, Willy Leimgruber, John William Scott, Donald Valentine, Jr.