Abstract

β-Cyclodextrin derivatives with varying lengths of π-conjugated arms have been synthesized. Their structures have been confirmed by 1H NMR, elemental analysis, mass spectrometry and X-ray crystal structure determination. Their self-inclusion properties are evaluated using Circular Dichroism, 1D and 2D 1H NMR measurements. It is found that, when the length of the π-conjugated arm is extended from 4 to 5 and to 6, the self-inclusion of the π-conjugated arm to the CD ring is enhanced. The effect of the self-inclusion on the optical properties of the CD-linked π-conjugated systems has been explored. Stronger inclusion leads to enhanced excitation-energy transfer.

Keywords: β-cyclodextrin, inclusion complex, π-conjugation, excitation energy transfer