<i>N′</i>‐(3‐Amino‐1<i>H</i>‐isoindol‐1‐ylidene)‐R‐carbohydrazides and Their Amide‐Type Isomerism

Abstract

Abstract A series of N′ ‐(3‐amino‐1 H ‐isoindol‐1‐ylidene)alkyl(aryl,heteroaryl)carbohydrazides have been synthesized in good yields and their structure and conformational behavior in the solid state and in solution have been studied by X‐ray crystallography, NMR spectroscopy, and quantum calculations. ( E )/( Z ) amide‐type isomerism and the dependence of the isomeric ratio upon steric effects and solvent polarity are discussed. The thermodynamic parameters of ( E ) → ← ( Z ) isomerization were determined by 1 H NMR dynamic spectroscopy. (© Wiley‐VCH Verlag GmbH &amp; Co. KGaA, 69451 Weinheim, Germany, 2006)