Preparation of tetrahydropyran-4-carboxylic acid and esters thereof

US5371246A · kind A · utility

Assignee

• BASF SE

Inventors

• Dirk Borchers · Birkenheide, DE
• Rolf Fischer · Heidelberg, DE
• Norbert Goetz
• Thomas Kuekenhoehner · Bischofswerda, DE
• Werner Schnurr · Herxheim, DE

Key dates

• Filing date: Aug 23, 1993
• Grant date: Dec 6, 1994
• Expiry date: Aug 23, 2013

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07D309/08
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

A process for the preparation of tetrahydropyran-4-carboxylic acid and esters thereof of the general formula I ##STR1## in which R.sup.1 denotes hydrogen, C.sub.1 -C.sub.6 alkyl, C.sub.5 -C.sub.8 cycloalkyl, or aryl by the reaction of a dihydro-2(3H)furanone of the general formula II ##STR2## in which R.sup.2 denotes hydrogen, C.sub.1 -C.sub.6 alkyl, or --CO--R.sup.3 and PA0 R.sup.3 denotes hydrogen or C.sub.1 -C.sub.6 alkyl, with water or an alcohol of the general formula III EQU R.sup.1 --OH (III), in which PA0 R.sup.1 has the aforementioned meaning, at temperatures ranging from 200.degree. to 350.degree. C. in the presence of a heterogenous acid catalyst, in which use is made of a fixed heterogenous acid catalyst.