300543-24-2Relevant articles and documents
Synthesis of 3-ethoxyisoxazole derivatives and 3-ethoxy-1H-pyrazole derivatives from β-oxo thionoesters
Ohta,Fujisawa,Nakai,Furukawa
, p. 1861 - 1864 (2007/10/03)
3-Ethoxyisoxazoles and 3-ethoxy-1H-pyrazoles were obtained in high yields from β-oxo thionoesters. The reaction of the ethyl β-oxo thionoesters with hydroxylamine hydrochloride in the presence of triethylamine at room temperature for 2 h gave the ethyl 3-oxopropiohydroximates and their hemiacetals, which were easily converted to the 3-ethoxyisoxazoles by refluxing for 3 h at pH 3-5. On the other hand, the reaction of the ethyl β-oxo thionoesters with hydrazine derivatives in the presence of triethylamine for 3-8 h at room temperature directly yielded the 3-ethoxy-1H-pyrazoles.
