NMR spectroscopic study and DFT calculations of vibrational analyses, GIAO NMR shieldings and 1JCH, 1JCC spin-spin coupling constants of 1,7-diaminoheptane

Vibrational frequencies and approximate mode descriptions of 1,7-diaminoheptane (dahp) have been determined via Becke-3-Lee-Yang-Parr (B3LYP) density functional method with 6-31G(d) basis set. 1H, proton coupled and uncoupled 13C, 15N, DEPT, COSY, HETCOR, INADEQUATE NMR spectra and the magnitude of one bond 1JCH, 1JCC coupling constants of dahp (C7H18N2) have been reported for the first time. 1H, 13C, 15N NMR chemical shifts and 1JCH, 1JCC coupling constants of dahp have been calculated by means of B3LYP density functional method with 6-311++G(d,p) basis set. Comparison between the experimental and the theoretical results indicates that density functional B3LYP method is able to provide satisfactory results for predicting vibrational frequencies and NMR properties.