Chiral recognition in bicyclic guanidines
A theoretical study of chiral recognition in bicyclic guanidines has been carried out by means of B3LYP/6-31+G(d,p) DFT calculations. A series of complexes between protonated 4,8-dimethyl-1,5,7-triazabicyclodecene (DTBD) and 2,5-disubtituted chiral cyclopentanones have been evaluated for chiral recognition, both in the gas phase and in benzene solution as per the polarizable continuum model (PCM) and analyzed by AIM and NBO methodologies. An inversion in the sense of chiral recognition has been observed between gas phase and solvated results for cyclopentanone complexes. Among the different correlations found (i.e. between electron density, hydrogen bond distance, second-order perturbation energy), a linear correlation has been established between thechiral recognition energy and different molecular parameters.