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:
Feb. 14, 1984
Filed:
Mar. 24, 1982
Lothar Janitschke, Kleinniedesheim, DE;
Werner Hoffmann, Neuhofen, DE;
Lothar Arnold, Heidelberg, DE;
Manfred Stroezel, Ilvesheim, DE;
Hans-Juergen Scheiper, Mutterstadt, DE;
BASF Aktiengesellschaft, Rheinland-Pfalz, DE;
Abstract
An improved process for the preparation of unsaturated ketones of the general formula I ##STR1## where R.sup.1 is --CH.sub.3, ##STR2## and R.sup.2 and R.sup.3 are different and each is H or --CH.sub.3, by reacting an aldehyde of the general formula II ##STR3## with a molar excess of acetone or methyl ethyl ketone at an elevated temperature in the presence of an aqueous alkali metal hydroxide solution, wherein (a) all the reactants are mixed thoroughly, (b) the temperature is kept at from 10 to 120.degree. C. above the boiling point of the lowest-boiling component and (c) the pressure is kept at from p to 100 bar, where p is the vapor pressure of the mixture at the reaction temperature. The products methylpseudoionone, dimethylpseudoionone, pseudoirone, methylpseudoirone and dimethylpseudoirone are useful scents and scent intermediates. In addition, pseudoionone is an important intermediate for the industrial preparation of vitamin A, and 6-methyl-hepta-3,5-dien-2-one is a sought-after aromatic.