Patents by Inventor Elmhart Neuber

Elmhart Neuber 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).

  • Solvent-free process for preparing 4-amino-2,2,6,6-tetramethylpiperidine
    Patent number: 5693817
    Abstract: A process for preparing 4-amino 2,2,6,6-tetramethylpiperidine (TAD) from 2,2,6,6-tetramethylpiperidone (TAA), ammonia and hydrogen using a cobalt or nickel catalyst on a support which allows the omission of any added solvent, and provides substantially simplified work-up and increased space-time yields by significantly reducing the amounts of excess ammonia and catalyst needed to accomplish the reaction.
    Type: Grant
    Filed: December 4, 1995
    Date of Patent: December 2, 1997
    Assignee: Huels Aktiengesellschaft
    Inventors: Stefan Frentzen, Elmhart Neuber, Gerhard Thelen