Method for producing chlorobenzoxazolene

US6274739A · kind A · utility

Assignee

• Aventis CropScience GmbH · DE

Inventors

• Hans-Joachim Ressel · Hattersheim, DE
• Mohammed Aslam · Mumbai, IN
• Jean-Pierre Demoute · Le Touquet-Paris-Plage, FR
• Gunter Schlegel · Liederbach, DE
• Wolfgang Welter · Hofheim, DE

Key dates

• Filing date: Jun 14, 2000
• Grant date: Aug 14, 2001
• Expiry date: Jun 14, 2020

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07D263/58
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

The invention relates to a process for preparing chlorobenzoxazoles of the formula (I), ##STR1## PA1 in which R.sup.1, R.sup.2 and R.sup.4 are as defined in claim 1 and PA1 in case (a) R.sup.3 =H, halogen, CN, NO.sub.2, C.sub.1 -C.sub.5 -alkyl, C.sub.1 -C.sub.5 -alkoxy, aryl or aryloxy, where each of the 4 lastmentioned radicals is unsubstituted or substituted, or PA1 in case (b) R.sup.3 =chlorine, PA1 which comprises reacting benzoxazoles of the formula (II), in which R.sup.1, R.sup.2 and R.sup.4 are as defined in formula (I) and R.sup.3 in case (a) is as defined in formula (I) and R.sup.3 in case (b) is hydrogen, PA1 in the presence of an acidic catalyst with a chlorinating agent to give the monochlorination product (I) or in case (b) with an excess of the chlorinating agent to give the dichlorination product (I) in which R.sup.3 =chlorine.