Patents by Inventor Harold L. Daughety

Harold L. Daughety 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: 4590292
    Abstract: A modified novel process for preparing cyclopropylamine from .gamma.-butyrolactone is described. The .gamma.-butyrolactone ring is cleaved with a hydrohalide in the presence of a novel catalyst comprising an aqueous sulfuric acid solution. The 4-chlorobutyric acid, thus formed is converted into a hindered chlorobutyrate ester. The hindered ester based on secondary and tertiary alkanols of eight or less carbon atoms, is cyclized to form the hindered cyclopropanecarboxylate ester by a novel reaction medium consisting of solid caustic in a water-immiscible solvent and a phase transfer catalyst. The hindered cyclopropanecarboxylate ester is ammoniated to form cyclopropanecarboxamide by a novel catalyst comprising an alkali metal salt of a polyol having hydroxy groups on adjacent carbons. The carboxamide formed in substantially quantitative yields is converted to cyclopropylamine by a modified Hofmann reaction utilizing continuous degradation of the intermediate with simultaneous distillation.
    Type: Grant
    Filed: June 10, 1985
    Date of Patent: May 20, 1986
    Assignee: Ciba-Geigy Corporation
    Inventors: Joseph T. Blackwell, Harold L. Daughety, Henry C. Grace, Ward H. Oliver