Patents by Inventor Hermann Richtzenbain

Hermann Richtzenbain 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).

  • Method of preparing malonic acid dialkyl esters
    Patent number: 4443624
    Abstract: Production of malonic acid dialkyl esters by reacting halogen acetic acid alkyl ester with carbon monoxide, and alkali metal alcoholate, alkaline earth metal alcoholate or a solution of alkali metal hydroxide in an alcohol at a pH of up to 8.5 in the presence of a cobalt compound which is a catalyst for the reaction.
    Type: Grant
    Filed: April 5, 1982
    Date of Patent: April 17, 1984
    Assignee: Dynamit Nobel AG
    Inventors: Uwe Prange, Moustafa El Chahawi, Wilhelm Vogt, Hermann Richtzenbain