Difluoromethyl nitril oxide (CF2HCNO): overseen chemical reagent
Eur. J. Org. Chem. 2017, 27, 3935-3940
A novel chemical reagent – difluoromethyl nitrile oxide, CF2HCNO – was generated in situ for the first time. The synthesis commenced with ethyl difluoroacetate and included only two chemical steps. The difluoromethyl nitrile oxide smoothly participated in [3+2]‐cycloaddition reactions with alkynes and enamines to give CF2H‐isoxazoles; these products are promising cores for agrochemistry. A representative CHF2‐isoxazole was incorporated into the known fungicide Fluxapyroxad (BASF), and the synthesized analogue showed higher antifungal activity than the parent fungicide.