On the Aminolysis of Bis-Imidoylchlorides of Oxalic Acid. Part I. Reaction with Aromatic and Aliphatic Amines
The reaction between bis-imidoylchlorides 2 derived from oxalic acid and several aromatic and aliphatic amines was investigated. While primary aromatic amines need a thermical activation by refluxing, primary aliphatic amines give mainly at room temperature the amidines 3 in moderatly up to good yields.
Proceeding from enantiomeric pure amines e.g. (R)- or (S)-1-phenethylamine the new homochiral oxalic amidines 3y and 3z with C2-symmetry were obtained. Several secondary amines react with the bis-imidoylchloride 2a to give via intramolecular cycloacylation derivatives of isatine. The new synthesized amidines 3 perform systems with a strong molecular dynamic like prototropie and E/Z-interconversion. All new compounds described were characterized by elemental analysis and spectroscopic methods.