β-cyclodextrin as an end-to-end connector

Abstract

Interaction of beta-cyclodextrin (beta-CD) with a ditopic molecule having adamantane (AD) at one end and a pyromellitic diimide (PMDI) moiety at the other is studied. The AD moiety undergoes inclusion binding with the beta-CD cavity, and the PMDI undergoes binding with the primary rim of beta-CD. In an equimolar solution of beta-CD and the ditopic molecule in water, beta-CD accommodates both modes of complexation simultaneously, leading to the formation of long fibers. The fibers get entangled to give a supramolecular hydrogel with very high water content.