ChemInform Abstract: Rigid Molecular Tweezers: Preorganized Hosts for Electron Donor-Acceptor Complexation in Organic Solvents.

ChemInform Abstract

Eight nonmacrocyclic receptor molecules such as (VII) are synthesized (as shown for the parent compound (VIIa) in the scheme) including an asym. example (VIII). The asym. (VIII) exhibits atropisomerism. These molecules, e.g. (VII) and (VIII), are rigid and provide a ca. 7 Å interchromophore distance in the preorganized cleft which forms highly oriented complexes with fluorenone (IX) the association constants of which being dependent on the π-basicity of the host (from 149 M^-1 for (VIIb) to 697 M^-1 for (VIIe)). Dehydrogenation of (VII) by DDQ to the dibenz(c,h)acridines causes only little differences between molecular tweezers (VII) and their aromatic counterparts.