Method for preparing trion-bis(oxime ether) derivatives andrion-mono and trion-bis(oxime ether) derivatives obtained therewith

A process for preparing trione bis(oxime ether) derivatives of the formula I

• where the substituents have the following meanings:
• R1,R3 are each unsubstituted, partially or fully halogenated C1-C6-alkyl or C3-C6-cycloalkyl;
• R2,R4 are each unsubstituted C1-C4-alkyl or C2-C4-alkenyl-, C2-C4-alkynyl- or phenyl-substituted methyl and
• X is oxygen or N—OH,
• which comprises
• 1) reacting a dione of the formula II,
• where the substituents R1, R2 and R3 are each as defined above with an alcohol or diol in the presence of an acid to give a ketal of the formula III,
• where the substituents R5 and R6 are each C1-C6-alkyl, benzyl or C1-C3-haloalkyl or R5 and R6 together with the carbon and the two oxygen atoms of the ketal function form a ring A
• where the substituents and the index n have the following meanings:
• R7,R8,R11,R12 are each hydrogen, halogen, C1-C4-alkyl, C1-C3-haloalkyl, C1-C4-alkoxymethyl, C2-C4-alkenyl, C2-C4-alkynyl or phenyl, where the latter may be substituted by nitro or halogen;
• R9,R10 each have one of the meanings given for R7, R8, R11 or R12 and R9 and R10 together form an exo-methylene group or a carbonyl group and
• n is 0,1 or 2,
• 2) converting the resulting ketal III
• a) with an alkoxyamine of the formula R4O—NH2, where R4 is as defined above, or one of its acid addition salts, or
• b) with hydroxylamine or its acid addition salt and subsequent alkylation with an alkylating agent R4—L1, where R4 is as defined above and L1 is a nucleophilically replaceable leaving group, into the bisoxime ether ketal IV,
• where the substituents R1 to R6 are each as defined above, and
• 3) hydrolyzing the bisoxime ether ketal IV obtained in this manner in the presence of acid,
• a) to give the bisoxime ether ketone Ia,
• b) aminating it with hydroxylamine or its acid addition salt to give the bisoxime ether oxime Ib,