Effect of substitution on the intramolecular hydrogen bonding of 4-amino-3-penten-2-one: Ab initio, AIM and NBO studies

Several substituted 4-amino-3-penten-2-one derivatives have been theoretically investigated in order to study conjugative and/or steric effects on the molecular structure and intramolecular hydrogen bond strengths. The molecular geometry and intramolecular hydrogen bond energy of 4-amino-3-penten-2-one other derivatives were investigated with ab initio, AIM and NBO calculations carried out at the B3LYP/6-31G∗∗ level of theory. The nature of intramolecular hydrogen bond that is present in APO and its derivatives has been investigated by means of the Bader theory of atoms in molecules (AIM) and natural bond orbital (NBO) analysis.