Crystal structure of the dimeric β-cyclodextrin complex with 1,12-dodecanediol

The structure of the complex of beta-cyclodextrin (beta-CD) with 1,12-dodecanediol has been determined at 173 K and refined to a final R = 0.0615 based on 22,386 independent reflections. The complex crystallizes in the triclinic space group P (1) over bar with a = 17.926(4), b = 15.399(3), c = 15.416(3) Angstrom, alpha = 103.425(4), beta = 113.404(4), gamma = 98.858(4)degrees, D-c = 1.362 Mg cm(-3) and V = 3651.4(13) Angstrom(3) for Z = 1. One molecule of the diol is located as a guest in the hydrophobic cavity of a beta-CD-dimer, forming a [3]pseudorotaxane. The guest molecule shows a disorder over two positions. The hydroxyl groups of the diol emerge from the primary faces of the beta-CD dimer and form several hydrogen bonds with water molecules lying in the interstitial space, similarly to dimeric complexes of beta-CD with other alpha,omega-bifunctional guests. (C) 2003 Elsevier Science Ltd. All rights reserved.