Efficient Preparation Of N ',N '-1H-Isoindole-1,3-Diylidenedicarbohydrazides Via 1,1,3-Trichloro-1H-Isoindole, And Their Characterization

N',N ''-isoindole-1,3-diylidenedialkyl(aryl.heteroaryl)carbohydrazides were prepared in good yields via 1,1,3-trichloro-1H-isoindole, which was shown to be a versatile reagent for their synthesis. Tautomeric structure and conformational behaviour of dicarbohydrazides in solid state as well as in solution have been studied by X-ray crystallography, NMR spectroscopy and quantum calculations. The dependence of Z/E amide-type isomerism upon steric effects and solvent polarity is discussed. (C) 2009 Elsevier Ltd. All rights reserved.