Solid state inclusion compound of S-ibuprofen in β-cyclodextrin: structure and characterisation

Abstract

A crystalline inclusion complex was isolated from the reaction of β-cyclodextrin (βCD) with aqueous S-(+)-ibuprofen (S-Ibu). The existence of a true inclusion complex in the solid state was confirmed by a combination of powder X-ray diffraction (XRD), single crystal X-ray diffraction, thermogravimetric analysis (TGA), FTIR and ¹³C CP MAS NMR spectroscopies. The inclusion compound crystallises in the non-centrosymmetric monoclinic space group C2 with a 2∶1 host∶guest stoichiometry. The crystal structure consists of a head-to-head dimer of βCD molecules stacked along the crystallographic c axis, thus forming a slightly tilted channel-type structure.