Synthesis of 4,5-dihydro-1H-pyrazole derivatives based on 3-acetyl-5-nitropyridines
作者:Alena L. Stalinskaya、Daria F. Weber、Tulegen M. Seilkhanov、Ivan V. Kulakov
DOI:10.1007/s00706-021-02751-5
日期:2021.3
Claisen–Schmidt-type aldol-crotonic condensation of 3-acetyl-5-nitropyridine derivatives with various aromatic aldehydes was used for the preparation of pyridylchalcones. Cyclization of the latter with hydrazine hydrate in acetic acid afforded the corresponding N-acetyl derivatives of 4,5-dihydro-1H-pyrazole. Graphic abstract