Holding of planar chirality of pillar[5]arene by kinetic trapping using host-guest interactions with achiral guest solvents

We report a solvent-dependent switching and holding of planar chirality of pillar[5]arene with stereogenic carbons at both rims by host-guest complexation with achiral guest solvents. The planar chirality could be held for a given length of time at 25 degrees C in long linear guest solvents by kinetic trapping through host-guest complexation. The kinetic trapping worked at 25 degrees C, but not at 60 degrees C, thus a planar-chiral inversion using kinetic trapping based on host-guest complexation in the long linear solvents was demonstrated.