2,2 '-Dihydroxybenzil: A Stereodynamic Probe For Primary Amines Controlled By Steric Strain

A rational approach for generating 1,1'-binaphthalene-like axial chirality of a small organic receptor, 2,2'-dihydroxybenzil is presented. The receptor combines with 2 equiv of monodentate primary amines to form a diimine, of which axial chirality is controlled by steric strain with moderate (1.4:1) to good (4.7:1) stereoselectivity. The observed circular dichroism (CD) spectra have been closely simulated by TD-DFT computations and can be used for determining the absolute chirality and enantiomeric excess of primary amines.