Abstract:Isatin acylhydrazones with sterically hindered phenolic fragments were obtained. Their structures were determined using 1D and 2D 1 H and 13 C NMR spectroscopy and X ray diffraction. The products synthesized by condensation of isatin and 1 (3,5 di tert butyl 4 hydroxybenzyl) 1H indole 2,3 dione with 3 (3,5 di tert butyl 4 hydroxyphenyl)propiono hydrazide exist as E and Z isomers about the C=N bond. E-Z isomerization takes place in boiling ethanol. The E isomer of the condensation product from isatin and 3 (3,5… Show more
“…These conditions 25,26 allows in situ generation of the highly reactive p-quinone methide 4 which immediately undergoes addition of corresponding isatin 1a-d with formation of a carbonnitrogen bond (Scheme 2). It should be noted here that the reaction takes place despite the hindrance due to the methyl group at the 7 position of the isatin heterocycle.…”
Section: Scheme 1 Synthesis Of Novel Sterically Hindered Benzylisatimentioning