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.
本发明涉及一种改进的新型工艺和工艺中间体,用于制备化合物的羟
肟中间体(II),其中R1为氢、
氟或
氯,R2为甲基、乙基、甲氧基、乙氧基、三
氟甲基、三
氟甲氧基、
氰基、
氟、
氯或
溴。新型工艺包括将公式(VI)的
苯胺重氮化,将得到的重氮盐与公式(X)的异
丙烯酸酯反应,将得到的酮与有机
亚硝酸酯在
氯化氢存在下反应,以及用甲基化剂甲基化得到的酮羟
肟(VIII),并将得到的O-甲基酮羟
肟(IX)与羟
肟反应。公式(II)的化合物是高活性杀菌剂的中间体,属于
叠氮类杀菌剂。