Patents by Inventor Francis L. Shenton

Francis L. Shenton 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).

  • Patent number: 4338459
    Abstract: A diester of .alpha.-acetyl-.alpha.'-methylsuccinic acid is prepared in improved yield under substantially anhydrous process conditions which minimizes decomposition of that diester by reacting an acetoacetate ester with an .alpha.-halopropionate ester in a solvent mixture containing a non-polar, aprotic liquid, e.g., toluene, and a dipolar aprotic liquid, e.g., DMF, at from about C. to reflux temperature in the presence of a phase transfer agent, a catalytic amount of iodide ion and solid form, substantially anhydrous alkali metal base or basic salt. Further improvement is obtained when the completed reaction mixture is diluted with water and adjusted to pH 8 to 9, and when the DMF/acetoacetate ester ratios are between about 1.7 and 3. The resulting diesters can be used under the conditions of this invention as intermediates in processes for making ibuprofen by combining and reacting the .alpha.-acetyl-.alpha.
    Type: Grant
    Filed: March 5, 1981
    Date of Patent: July 6, 1982
    Assignee: The Upjohn Company
    Inventor: Francis L. Shenton
  • Patent number: 4072698
    Abstract: The present invention is a chemical method for obtaining an optically pure 2-aminonitrile or a 2-aminoamide from (1) an optically impure mixture, (2) a racemic mixture, or (3) the optically pure enantiomer of the opposite configuration, in an amount greater than actually present, by use of optically active acids with a ketone or an aldehyde catalyst. Yields of greater than 70 percent of one enantiomer are obtained from racemic mixtures in very short time periods.
    Type: Grant
    Filed: December 2, 1976
    Date of Patent: February 7, 1978
    Assignee: The Upjohn Company
    Inventors: Thomas A. Hylton, Francis L. Shenton