Patents Represented by Law Firm Spung Horn Kramer & Woods
  • Process for the preparation of organic carbonates having at least one aromatic ester group
    Patent number: 5362901
    Abstract: The title compounds are prepared from organic carbonates having at least one aliphatic ester group and phenolic compounds by transesterification in the presence of a transesterification catalyst known per se at 60.degree.-320.degree. C. in a column-type reactor with multiple recycling of the reaction products into this reactor with intermediate storage of the product streams.
    Type: Grant
    Filed: May 25, 1993
    Date of Patent: November 8, 1994
    Assignee: Bayer Aktiengesellschaft
    Inventors: Paul Wagner, Norbert Schon, Hans-Josef Buysch
  • Process for the preparation of p-dichlorobenzene
    Patent number: 5210343
    Abstract: Dichlorobenzene having an increased p-content and a greatly reduced m-content is obtained by ring chlorination of benzene or chlorobenzene in the presence of Friedel-Crafts catalysts if the reaction is carried out in the presence of co-catalysts of the formula (I) ##STR1## wherein X represents fluorine, chlorine, bromine, trifluoromethyl or pentafluoroethyl andA represents 2 hydrogen atoms or the group --CH.dbd.CH--CH.dbd.CH--.
    Type: Grant
    Filed: March 19, 1992
    Date of Patent: May 11, 1993
    Assignee: Bayer Aktiengesellschaft
    Inventors: Franz-Josef Mais, Helmut Fiege