A convenient synthesis of functionalized pyrazolones bearing a highly twisted 1, 3-butadiene moiety with skew geometry. Issue 19 (2nd October 2018) - Yavari, Issa
Abstract: The four-component reaction among arylhydrazine, alkyl acetoacetate derivatives, alkyl isocyanides, and dialkyl acetylenedicarboxylates, leading to the formation of dialkyl 2-[( Z )-(alkylamino)(3-alkyl-5-oxo-1-phenyl-1, 5-dihydro-4 H -pyrazol-4-ylidene)methyl] fumarates is described. The structure of target compounds was confirmed using X-ray diffraction study. These pyrazolone derivatives contain a highly twisted exocyclic 1, 3-butadiene moiety with skew ( ϕ = 87°) geometry. Graphical Abstract: