Vibrational, NMR and quantum chemical investigations of acetoacetanilde, 2-chloroacetoacetanilide and 2-methylacetoacetanilide

The FTIR and FT-Raman spectra of acetoacetanilide (AAA), 2-chloroacetoacetanilide (2CAAA) and 2-methylacetoacetanilide (2MAAA) have been analysed. Quantum chemical studies were performed with B3LYP method using 6-311++G** and cc-pVTZ basis sets. The structural parameters, energies, thermodynamic parameters, vibrational frequencies and the NBO charges were determined. The 1H and 13C isotropic chemical shifts (δ ppm) with respect to TMS were also calculated using the gauge independent atomic orbital method. The delocaliation energy of the different types of bonding interactions was investigated. The influences of chloro and methyl groups on the characteristic frequencies of amide (CONH) have been discussed.