Quantitative description of optical activity using the principle of pairwise interactions: 2,2′-spirobi-indanes

Abstract

The molar rotations [M]₅₈₉ of chiral, optically active tri- and tetra-substituted 2,2′-spirobi-indanes are described by means of Kauzmann's Principle of Pairwise Interactions (PPI). Additionally, the relation derived from the PPI gives encouraging results for the description of the circular dichroism. The results obtained are compared with those gained by means of the Theory of Chirality Functions (TCF). Furthermore, Kauzmann's theory gives evidence as to which classes of molecules might benefit from application of a semiempirical method for the quantitative description of chiroptical properties. Thus, the great success of the TCF for classes of compounds with D_2d symmetry of the skeleton is due to the cancellation of all (pairwise) ligand–core interaction terms by symmetry.