Synthesis of 3-Substituted Arylpyrazole-4-carboxylic Acids
作者:A. V. Lebedev、A. B. Lebedeva、V. D. Sheludyakov、E. A. Kovaleva、O. L. Ustinova、I. B. Kozhevnikov
DOI:10.1007/s11176-005-0318-7
日期:2005.5
3-aryl-substituted pyrazole-4-carboxylic acids, involving Vilsmeier formylation of semicarbazones of 26 available mono- and disubstituted acetophenones and 2-acetylthiophene followed by oxidation of the resulting 3-aryl-substituted pyrazole-4-carboxaldehydes under the action of potassium permanganate. The mechanism of the formylation reaction is discussed. The method successfully works even with acetophenones