Synthesis, physicochemical and vibrational spectral properties of 2–pyridone and 2–aminopyridine derivatives: An experimental and theoretical study

A convenient and efficient one–pot three–component reaction of acetyl acetone, malononitrile and ammonium acetate was investigated for the synthesis of 3–cyano–4,6–dimethyl–2–pyridone (PI) and 2–amino–3–cyano–4,6–dimethylpyridine (PII). The products were achieved with high purity, high yields and short reaction time. The yields of the two products depend on the concentration of ammonium acetate, reaction time and the solvent used. The structures of the isolated products were confirmed by elemental analysis and spectral data, supported by quantum chemical (MP2) calculations, both in gas phase and solvents (water and ethanol), that were also employed to track the reaction mechanisms and model vibrational spectral properties for final characterization and interpretation of spectral data. A remarkable matching between theoretical predictions and experiments was attained both for the geometrical parameters, as compared to X-Ray data available in the literature, and for vibrational frequencies, leading to a correlation coefficient (R2) of 0.99. Molecular docking was further studied to predict the docking binding energy of the synthesized compounds with the target proteins.