Preparation of aldehydes

US5679869A · kind A · utility

Assignee

• BASF SE

Inventors

• Werner Schnurr · Herxheim, DE
• Rolf Fischer · Heidelberg, DE
• Joachim Wulff-Doring · Bischofswerda, DE
• Michael Hesse · Westlake Village, US

Key dates

• Filing date: Dec 5, 1995
• Grant date: Oct 21, 1997
• Expiry date: Dec 5, 2015

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07C45/41
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

A process for preparing aldehydes of the general formula I ##STR1## where R.sup.1, R.sup.2 and R.sup.3 are each hydrogen, C.sub.1 -C.sub.6 -alkyl, C.sub.3 -C.sub.8 -cycloalkyl, aryl, C.sub.7 -C.sub.12 -alkylphenyl, C.sub.7 -C.sub.12 -phenylalkyl and R.sup.1 and R.sup.2 are joined together to form a 3-, 4-, 5-, 6- or 7-membered cycloaliphatic ring, PA1 R.sup.1 and R.sup.3 are each C.sub.1 -C.sub.4 -alkoxy, phenoxy, methylamino, dimethylamino or halogen, and PA1 R.sup.1 is additionally hydroxyl or amino comprises reacting a carboxylic acid or ester of the general formula II ##STR2## where R.sup.1, R.sup.2 and R.sup.3 are each as defined above, and PA1 R.sup.4 is hydrogen, C.sub.1 -C.sub.6 -alkyl, C.sub.3 -C.sub.8 -cycloalkyl, aryl, C.sub.7 -C.sub.12 -alkylphenyl or C.sub.7 -C.sub.12 -phenylalkyl, with hydrogen in the gas phase at temperatures from 200.degree. to 450.degree. C. and pressures from 0.1 to 20 bar in the presence of a catalyst whose catalytically active mass comprises from 60 to 99.9% by weight of zirconium oxide and from 0.1 to 40% by weight of one or more elements of the lanthanides.