Patent ID: 6603025
Filing Date: 2003-08-05
Classification: C07D

Abstract:
A process for preparing a compound of the Formula (I), whereinR1 represents hydrogen or alkyl and R2, R3, R4 and R5 are identical or different and independently of one another each represents hydrogen, alkyl, alkoxy, halogenoalkyl or halogen, comprising the steps of:a) hydrolyzing a compound of the Formula (II), â€ƒwherein R2, R3, R4 and R5 are each as defined above R6 represents alkyl using an acid, optionally in the presence of a diluent, resulting in the formation of a benzofuranone of the Formula (III), â€ƒwherein R2, R3, R4 and R5 are each as defined above, and b) reacting said benzofuranone of the Formula (III) without work-up with a member selected from the group consisting of a hydroxylamine derivative of the Formula (IV), H2Nâ€”Oâ€”R1â€ƒâ€ƒ(IV) â€ƒwherein R1 is as defined above, and an acid addition complex thereof, optionally in the presence of a diluent and optionally in the presence of a buffer medium, whereupon said compound of said Formula (I) is formed.