Patents by Inventor Thomas-Michael Kahl

Thomas-Michael Kahl 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: 5616771
    Abstract: A process for preparing an aryl chloroformate is disclosed that involves the reaction of a phenol with phosgene in the presence of a cyclic urea.
    Type: Grant
    Filed: May 16, 1996
    Date of Patent: April 1, 1997
    Assignee: BASF Aktiengesellschaft
    Inventors: Thomas-Michael Kahl, Thomas Wettling
  • Patent number: 5359082
    Abstract: A process for the preparation of 4-substituted imidazoles of the general formula ##STR1## in which R denotes C.sub.1 -C.sub.20 alkyl, C.sub.3 -C.sub.20 cycloalkyl, aryl, and C.sub.7 -C.sub.20 aralkyl,whereina) N-formyl-.alpha.-aminonitriles of the general formula I ##STR2## in which R has the meanings stated above and A stands for carbonyl, are reacted, at a temperature ranging from 20.degree. to 200.degree. C. and a pressure ranging from 20 to 500 bar, with hydrogen in the presence of hydrogenation catalysts andb) the resulting N-formyl-1,2-diamines of the general formula ##STR3## in which R and A have the meanings stated above and n stands for 0 or 1, are reacted over a cyclization/dehydrogenation catalyst at a temperature ranging from 200.degree. to 600.degree. C. and a pressure ranging from 0.001 to 5 bar.
    Type: Grant
    Filed: March 23, 1993
    Date of Patent: October 25, 1994
    Assignee: BASF Aktiengesellschaft
    Inventors: Ulrich Koehler, Thomas-Michael Kahl, Horst Neuhauser, Hardo Siegel, Michael Kroener
  • Patent number: 5196611
    Abstract: The preparation of an alkyl, alkenyl, or alkynyl chloride by the reaction of a corresponding alcohol with phosgene or thionyl chloride in the presence of a phosphine oxide acting as catalyst, wherein the catalyst used is an aliphatic, cycloaliphatic, or cyclic/aliphatic phosphine oxide.
    Type: Grant
    Filed: May 6, 1992
    Date of Patent: March 23, 1993
    Assignee: BASF Aktiengesellschaft
    Inventors: Jochem Henkelmann, Irene Troetsch-Schaller, Thomas Wettling, Thomas-Michael Kahl, Leopold Hupfer, Wolfgang Franzischka, Hermann Koehler
  • Patent number: 4950756
    Abstract: 1-Nitroanthraquinone-2-carboxylic acid of the formula I ##STR1## is prepared by treating novel 2-substituted 1-nitroanthraquinones of the general formula II ##STR2## where R is --CH.dbd.CH--R.sup.1 or --CH.sub.2 --CHO, where R.sup.1 is C.sub.1 -C.sub.5 -dialkylamino or a cyclic 5- or 6-membered amine which may contain further hetero atoms, with oxidizing agents free of heavy metal.
    Type: Grant
    Filed: October 30, 1989
    Date of Patent: August 21, 1990
    Assignee: BASF Aktiengesellschaft
    Inventors: Jochem Henkelmann, Helmut Hoch, Thomas-Michael Kahl, Gerhard Kilpper, Walter Maier