Patents by Inventor Peter Labuhn

Peter Labuhn 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: 4267356
    Abstract: A process is described for the preparation of N-(1'-alkoxycarbonylethyl)-2,6-dialkylanilines of the formula ##STR1## in which R.sub.1 and R.sub.2 are each methyl or ethyl and R.sub.3 is an alkyl group having 1 to 4 carbon atoms, this process being based on the reaction of a corresponding 2,6-dialkylaniline with a corresponding alkyl 2-chloropropionate or alkyl 2-bromopropionate. The process is carried out by carrying out the reaction of the 2,6-dialkylaniline with the 2-halogenopropionic acid ester at 110.degree.-130.degree. C. in the presence of an alkali metal iodide as the catalyst, and of an alkali metal carbonate or alkali metal bicarbonate as an acid acceptor, in excess 2,6-dialkylaniline as the solvent, removing, by distillation, the water formed during the reaction and working up the organic phase, which is obtained after adding water and separating the phases, by distillation.
    Type: Grant
    Filed: June 9, 1980
    Date of Patent: May 12, 1981
    Assignee: Ciba-Geigy Corporation
    Inventors: Alfred Grieder, Klaus-Jurgen Coers, Peter Labuhn
  • Patent number: 4035423
    Abstract: A new process for the production of 3,4-dialkoxyanilines in which the two alkyl groups are different from each other is disclosed. The process comprises the stepwise introduction of the alkyl groups in different stages of the process by converting pyrocatechol into its monoalkyl ether, coupling said monoalkyl ether with a phenyldiazonium salt, alkylating the 3-alkoxy-4-hydroxy-azobenzene obtained to form 3,4-dialkoxyazobenzene and reductively cleaving the latter to the corresponding 3,4-dialkoxyaniline. The 3,4-dialkoxyanilines obtainable by the new process are valuable intermediates for the preparation of 4-hydroxy-6,7-dialkoxy-3-quinoline carboxylic acid esters which are excellent coccidiostats.
    Type: Grant
    Filed: February 20, 1976
    Date of Patent: July 12, 1977
    Assignee: Ciba-Geigy Corporation
    Inventors: Jean-Jacques Gallay, Ernst Aufderhaar, Peter Labuhn