Absolute configuration of axially chiral bisquinolones: DFT calculations and X-ray crystallography

The absolute configuration of axially chiral bisquinolones is established by comparison of experimental CD spectra and those simulated on the basis of TDDFT calculation. Specifically, the previous ambiguous assignment for 3,3′-dibromo-6,6′,7,7′-tetramethoxy-4,4′-biscarbostyril could be resolved as aR axial chirality for the first eluted enantiomer. The computational findings are corroborated by X-ray crystallography.