GIAO calculations of chemical shifts in enantiometrically pure 1-trifluoromethyl tetrahydroisoquinoline alkaloids

Isotropic 1H and 13C nuclear magnetic shielding constants of enantiometrically pure 1-trifluoromethyl tetrahydroisoquinoline alkaloids have been calculated by employing the gauge-including-atomic-orbital (GIAO) method at the B3LYP density functional level of theory. Geometry of each compound has been optimized employing 6-31G(d,p) and 6-311G basis sets. The theoretical trends are compared with experimental data taken from the literature. The least squares regression analyses of the results indicate R-square values greater than 0.82 in the range for total data set.