Electronic structure investigations of 1-amino-2,6-dimethylpiperidine by NMR spectral studies by ab initio and DFT calculations

Abstract

In this work, a combined experimental and theoretical study on molecular structure, vibrational spectra of 1-amino-2,6-dimethylpiperidine (ADP) has been reported. The FTIR and FT-Raman spectrum have been recorded in the region 4000-400 cm^-1 and 3500-50 cm^-1, respectively. The molecular geometry, harmonic vibrational frequencies and bonding features of ADP have been calculated by using ab initio/HF and density functional theory/B3LYP methods with 6-31+G(d,p) basis set. A detailed interpretation of the FTIR, FT-Raman, NMR spectra of ADP has also been reported. Natural bond orbital analysis has been carried out to explain the charge transfer or delocalization of charge due to the intra-molecular interactions. Energy of the highest occupied molecular (HOMO) orbital and lowest unoccupied (LUMO) molecular orbital have been predicted.