PURPOSE: To obtain the title compound useful as an intermediate for fungicide ad herbicide, in short reaction steps and high yield, by reacting dimethylformamide with phosgene and reacting the product with a hydrazone derivative.
CONSTITUTION: Dimethylformamide is made to react with phosgene in excess dimethylformamide or in an inert solvent (preferably halogenated hydrocarbon, especially chloroform, dichloromethane or their mixture) at 0W100°C, preferably 0W50°C to obtain a Vilsmeier reagent. A compound of formula II (R1 and R2 are lower alkyl) is dripped into the Vilsmeier reagent -10W+50°C, preferably 0W10°C and the components are made to react with each other at 0W100°C, preferably 60W90°C to obtain the objective compound of formula II having excellent properties as a fungicide for blight and downey mildew. The objective compound can be produced from the above reagent in high yield and site- selectivity in one step.
TOMITANI KANJI
SHIMOTORI HITOSHI
TANAKA YOSHINORI
ISHIKAWA KATSUTOSHI
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