Method for producing 6,10 and 6,9-dimethyl-5,10-undecadienyl-2-ones

US6310259A · kind A · utility

Assignee

• Degussa AG · DE

Inventors

• Wilhelm Keim · Aachen, DE
• Armin Kraus · Aachen, DE
• Rainer Hahn · Tübingen, DE
• Klaus Huthmacher · Gelnhausen, DE

Key dates

• Filing date: Mar 23, 2000
• Grant date: Oct 30, 2001
• Expiry date: Mar 23, 2020

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07C67/347
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

The present application refers to a process for preparing 6,10- and 6,9-dimethyl-5,10-undecadienyl-2-ones by telomerizing isoprene with alkyl acetoacetates in the presence of a catalyst system containing a transition metal compound catalyst and a phosphorus- or arsenic-containing compound cocatalyst, wherein the process is performed in the presence of a protic additive of the general formula ##STR1## in which: PA1 R.sup.1, R.sup.2, R.sup.3 represent an alkyl group with 1 to 9 carbon atoms, branched or unbranched, a cycloalkyl group with 6 to 8 carbon atoms, an aryl group, in particular phenyl, or an arylalkyl group, PA1 X.sup.(-) represents an inorganic or organic anion, PA1 y is 1 or 2, and the .beta.-ketoester so obtained is saponified and decarboxylated in a manner known per se.