Formation of 3Pseudorotaxanes from β-cyclodextrin and a Series of Dicarboxylic Acids with Their Corresponding α,ω-alkanedicarboxylate Anions

Inclusion complexes between β-cyclodextrin (β-CD) and a series of dicarboxylic acids (DAn, n=11-15) were prepared by co-grinding and co-precipitation methods and the 3pseudorotaxane structure of them was eluci-dated by FTIR, DTA and XRD characterizations. Inclusion complexes of β-CD and α，w-alkanedicarboxylate anions (DAn2-) were acquired by neutralizing β-CD/DAn different inclusion complexes with sodium hydrox-ide and the structure was also proved to be a pseudorotaxane structure by 1H-NMR spectra and NOESY spectrum. Both the inclusion complexes of β-CD/DAn and β-CD/DAn2- adopt the 3pseudorotaxane structure with β-CD arranged in dimers threaded onto one aliphatic chain and the binding mode of 1:1 inclusion complex was excluded based on the consideration of chain conformations