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Updated: Apr 20, 2026
Facile Preparation of 4-Substituted Quinazoline Derivatives
Published on: February 15, 2016
Nuclear magnetic resonance, vibrational spectroscopic studies, physico-chemical properties and computational
M A Pasha1, Aisha Siddekha2, Soni Mishra3
1Department of Studies in Chemistry, Central College Campus, Bangalore University, Bangalore 560001, India.
Abstract:
In the present study, 2'-nitrophenyloctahydroquinolinedione and its 3'-nitrophenyl isomer were synthesized and characterized by FT-IR, FT-Raman, (1)H NMR and (13)C NMR spectroscopy. The molecular geometry, vibrational frequencies, (1)H and (13)C NMR chemical shift values of the synthesized compounds in the ground state have been calculated by using the density functional theory (DFT) method with the 6-311++G (d,p) basis set and compared with the experimental data. The complete vibrational assignments of wave numbers were made on the basis of potential energy distribution using GAR2PED programme. Isotropic chemical shifts for (1)H and (13)C NMR were calculated using gauge-invariant atomic orbital (GIAO) method. The experimental vibrational frequencies, (1)H and (13)C NMR chemical shift values were found to be in good agreement with the theoretical values. On the basis of vibrational analysis, molecular electrostatic potential and the standard thermodynamic functions have been investigated.
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