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:
Jun. 29, 1999
Filed:
Dec. 12, 1997
Geertrudes H Suverkropp, Geleen, NL;
Paulus L Alsters, Sittard, NL;
Carina S Snijder, Sittard, NL;
Johannes G De Vries, Maastricht, NL;
DSM N.V., TE Heerlen, NL;
Abstract
Process for the preparation of a heterocyclic o-dicarboxylic acid containing at least one N atom, in which a corresponding benzo-fused heterocyclic compound containing at least one N atom is oxidised in the presence of hydrogen peroxide, a Bronsted acid and an iron compound. Preferably Fe(NO.sub.3).sub.3 is used as the iron compound and HNO.sub.3 as the Bronsted acid. The amount of iron compound to be used preferably lies between 0.1 and 2 mol. %, relative to the amount of employed benzo-fused heterocyclic compound containing at least one N atom. Even higher yields can be obtained if a copper compound or an organic electron-transferring compound is also used, in addition to the iron compound. In particular, the process according to the invention can be used to prepare 2,3-pyridine dicarboxylic acids from corresponding quinoline compounds.