Beschreibung:
<jats:p><jats:bold>NMR Investigations on the Structure of Substituted 3‐Aminoacrylic Esters</jats:bold></jats:p><jats:p>3‐Amino‐2‐cyano‐3‐methoxyacrylate <jats:bold>1</jats:bold> and 3‐amino‐3‐chloro‐2‐cyanoacrylate <jats:bold>2</jats:bold> exist in the <jats:italic>E</jats:italic> configuration (<jats:bold>1a, 2a</jats:bold>), which is stabilized by intramolecular hydrogen bonds. <jats:sup>1</jats:sup><jats:italic>J</jats:italic>(<jats:sup>15</jats:sup>N, <jats:sup>1</jats:sup>H)‐coupling constants give no evidence for an equilibrium between enamine‐ (<jats:bold>1a, 2a</jats:bold>) and imino semiacetal (<jats:bold>1b, 2b</jats:bold>) tautomers.</jats:p>