STRUCTURE OF A BETA-CYCLODEXTRIN VANILLIN INCLUSION COMPLEX

Vanillin was found to form a stable complex with β-cyclodextrin. A binding constant value of 1.11 X 104M-1was determined for the 1:1 complex.-1H NMR chemical shift differences and circular dichroism spectra indicated that both phenolic end and aldehyde end were affected by complexation. 2D nuclear Overhauser enhancement spectroscopy indicated proximity of OCH3 in vanillin to the anomeric protons of β -cyclodextrin. 1D difference NOE experiments have revealed that vanillin exists with the phenolic end nearer to the narrower end and the aldehyde end to the wider end of the torusshaped β -cyclodextrin molecule. © 1990, American Chemical Society. All rights reserved.