Preparation of unsaturated ketones

US6184420A · kind A · utility

Assignee

• BASF SE

Inventors

• Joaquim Henrique Teles · Waldsee, DE
• Norbert Rieber · Mannheim, DE
• Klaus Breuer · Speyer, DE
• Dirk Demuth · Schallstadt, DE
• Hartmut Hibst · Schriesheim, DE
• Stefan Kaeshammer · Schifferstadt, DE
• Heinz Etzrodt · Neustadt, DE
• Wulf Kaiser · Bad Dürkheim, DE

Key dates

• Filing date: Sep 10, 1998
• Grant date: Feb 6, 2001
• Expiry date: Sep 10, 2018

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y02P20/582
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

Unsaturated ketones of the formulae Ia and Ib ##STR1## are prepared by a process consisting of the combination of the following reactions: a) The conventional reaction of an allyl alcohol of the formula IIa or a propargyl alcohol of the formula IIb ##STR2## with an isopropenyl ether of the formula III ##STR3## with formation of a ketal of the formula IV ##STR4## as a byproduct, b) preparation of the isopropenyl ether of the formula III by reacting a ketal of the formula IV with propyne or allene, or a mixture thereof in the gas phase at elevated temperatures in the presence of a heterogeneous catalyst containing zinc or cadmium together with silicon or oxygen, and c) feeding the ketal of the formula IV formed in the reaction (a) into stage (b) for the preparation of the isopropenyl ether of the formula III again.