The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 04, 1992
Filed:
Aug. 16, 1991
Michael Meier, Frankfurt am Main, DE;
Wolfgang Tronich, Eppstein, DE;
Hoechst Aktiengesellschaft, Frankfurt am Main, DE;
Abstract
A process for the preparation of aromatic sulfonyl chlorides of the formula I ##STR1## in which R.sub.1, R.sub.2 and R.sub.3 are identical or different and are hydrogen, fluorine, chlorine, bromine or iodine atoms, alkyl(C.sub.1 -C.sub.4), acetamido, nitro or carboxyl groups, or R.sub.1 and R.sub.2 together form an aromatic or heteroaromatic ring having 5 or 6 ring members, which can be substituted by fluorine, chlorine, bromine or iodine atoms, alkyl(C.sub.1 -C.sub.4), acetamido, nitro or carboxyl groups, by reaction of aromatic compounds of the formula II ##STR2## in which R.sub.1, R.sub.2 and R.sub.3 have the abovementioned meanings, with chlorosulfonic acid in excess or with chlorosulfonic acid or oleum and thionyl chloride, by reacting in the presence of sulfamic acid as a catalyst.