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. 21, 1994
Filed:
Sep. 08, 1993
Rolf Drewes, Lindenfels, DE;
Hans-Helmut Friedrich, Lautertal, DE;
Ciba-Geigy Corporation, Ardsley, NY (US);
Abstract
There is disclosed a process for the preparation of an alpha-aminoketone salt of formula I ##STR1## which comprises reacting a nitrosated keto ester of formula II ##STR2## with a carboxylic anhydride of formula IV ##STR3## under the conditions of catalytic hydrogenation, to a compound of formula III ##STR4## which compound of formula III is then hydrolysed with an acid H.sub.n A to the salt I, in which formulae above R.sub.1 is C.sub.1 -C.sub.6 alkyl, phenoxy-C.sub.1 -C.sub.4 alkyl, phenyl, C.sub.7 -C.sub.9 phenylalkyl, or phenyl or C.sub.7 -C.sub.9 phenylalkyl which are substituted by halogen, C.sub.1 -C.sub.6 alkyl or C.sub.1 -C.sub.6 alkoxy, hydroxy or cyano, R.sub.2 is C.sub.1 -C.sub.4 alkyl or cyclohexyl, n is 1 to 3, R.sub.3 is C.sub.1 -C.sub.4 alkyl and A is the radical of an organic or mineral protic acid. Pyrroles suitable as co-stabilisers for PVC can be prepared from alpha-aminoketone salts of formula I.