STEREOCHEMISTRY OF α-AMINOACETOPHENONE OXIMES STUDY OF SOLVENT EFFECTS

Article abstract of DOI:10.1016/S0040-4020(01)86809-5

The aminolysis of Z-α-halogenoacetophenone oximes results in different mixtures of E- and Z-α-aminoacetophenone oximes depending on the solvent used.Assignment of configuration can be achieved by ¹³C NMR spectroscopy even if only one isomer is available using a strong solvent dependence of the methylene chemical shift in the case of the Z-isomers.This effect is due to the presence of different conformations in the solvents chloroform and dimethyl sulfoxide.Together with a study by vapor pressure osmometry the results provide an unambiguous proof of intramolecular hydrogen bonding of Z-α-aminoacetophenone oximes in chloroform.