Preparation of 5-membered ring heterocycles

US5453516A · kind A · utility

Assignee

• BASF SE

Inventors

• Rolf Fischer · Heidelberg, DE
• Rolf Pinkos · Bad Dürkheim, DE

Key dates

• Filing date: Dec 13, 1993
• Grant date: Sep 26, 1995
• Expiry date: Dec 13, 2013

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07D315/00
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

A process for preparing 5-membered ring heterocycles of the general formula I ##STR1## where R.sup.1 is methyl or hydroxyethyl, PA1 R.sup.2,R.sup.3,R.sup.4,R.sup.5 and R.sup.6 are hydrogen, C.sub.1 - to C.sub.12 -alkyl, C.sub.2 - to C.sub.12 -alkenyl, aryl, C.sub.3 - to C.sub.8 -cycloalkyl, C.sub.1 - to C.sub.12 -alkoxy, halogen, C.sub.2 - to C.sub.20 -alkoxycarbonylalkyl, C.sub.2 - to C.sub.20 -alkylcarbonyloxy, formyl, C.sub.2 - to C.sub.20 -formylalkyl, benzoyl or --CH(OR.sup.3)(OR.sup.5), or R.sup.3 and R.sup.5 together are a C.sub.2 - to C.sub.7 -alkylene chain which is unsubstituted or monosubstituted to pentasubstituted by R.sup.4 or a .dbd.CH--CH.dbd.CH--CH.dbd. unit which is unsubstituted or monosubstituted to tetrasubstituted by R.sup.4, PA1 X is oxygen or N--R.sup.4 by reacting 5-membered ring heterocycles of the general formula II ##STR2## where R.sup.2, R.sup.3, R.sup.4, R.sup.5, R.sup.6 and X have the abovementioned meanings and Y is hydrogen, acetyl or C.sub.2 - to C.sub.20 -alkoxycarbonyl, with dimethyl or ethylene carbonate in the presence of a nitrogen-containing base at from 50.degree. to 300.degree. C. and from 0.01 to 50 bar is described.