Process for the preparation of strobilurin intermediates
AssigneeBayer Aktiengesellschaft
InventorsRudolf Waditschatka, René Zurflüh, Edward Kelsall, Hugo Ziegler, Linhua Wang
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AssigneeBayer Aktiengesellschaft
InventorsRudolf Waditschatka, René Zurflüh, Edward Kelsall, Hugo Ziegler, Linhua Wang
Estimating the term…
The present invention relates to a novel improved process and intermediates for the process of preparing the oxime intermediates of formula (II) wherein R1 is hydrogen, fluoro or chloro, and R2 is methyl, ethyl, methoxy, ethoxy, trifluoromethyl, trifluoromethoxy, cyano, fluoro, chloro or bromo. The novel process comprises diazotizing an aniline of formula (VI) reacting the resulting diazonium salt with isopropenylacetate of formula (X) and reacting the resulting ketone of formula (XI) with an organic nitrite in the presence of hydrogene chloride, and methylating the resulting ketooxime of formula (VIII) with a methylating agent and reacting the resulting O-methyl ketooxime of formula (IX) with hydroxylamine. The compounds of formula (II) are intermediates for highly active fungicides from the class of the strobilurins.
A process for preparing an oxime of formula II
Dependencies are inferred from the claim text.