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US 6,603,025 B1Granted
Method of production of benzofuranone oximes
AssigneeBayer Aktiengesellschaft
InventorsReinhard Lantzsch, Herbert Gayer, Peter Gerdes, Walter Hübsch, Lubbertus Mulder, Bernd Gallenkamp, Matthias Decker
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Abstract
The present invention relates to a novel process for preparing known benzofuranone oximes, and to a novel process for preparing known benzofuranyl alkanoates which are used as intermediates in the synthesis sequence.
Claims8
A process for preparing a compound of the Formula (I),
- wherein
- R1 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),
- wherein
- 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),
- wherein
- 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),
- H2N—O—R1 (IV)
- wherein
- 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.
12 more elements
A process for preparing a compound of the Formula (II),
- wherein
- R2, R3, R4 and R5 are identical or different and independently of one another each represents hydrogen, alkyl, alkoxy, halogenoalkoxy or halogen, and
- R6 represents alkyl,
- comprising the step of:
- reacting a compound of the Formula (V),
- wherein
- R2, R3, R4, R5 are each as defined in this claim 5 above, with
- a member selected from the group consisting of an aliphatic acid anhydride of the Formula (VI)
- wherein
- R6 is as defined above in this claim 5
- and an aliphatic acyl chloride of the Formula (VII),
- wherein
- R6 is as defined above in this claim 5, in the presence of a catalyst, whereupon the compound of the Formula (II) is formed.
10 more elements
Dependencies are inferred from the claim text.