1: 4-bromo-3,5-dimethylisoxazole With diisobutylaluminium hydride; magnesium; lithium chloride; zinc(II) chloride in tetrahydrofuran T=23°C; Inert atmosphere; 2: trichloromethylcarbonyl isocyanate in tetrahydrofuran T=-20 - 25°C; Inert atmosphere; 3: With methanol; potassium carbonate in tetrahydrofuran T=25°C; 12 h; Inert atmosphere;

ammonium hydroxide

thionyl chloride Heating;