Formation and polymorphic phase transitions of crystalline inclusion compounds between 2,2′‐bis(9‐hydroxy‐9‐fluorenyl)biphenyl host and acetone guest
Аннотация
Abstract The 2,2′‐bis(9‐hydroxy‐9‐fluorenyl)biphenyl host compound ( 1 ) was found to form various crystalline inclusion compounds with acetone depending on the crystallization conditions or on the method of preparation (inclusion of acetone vapour, co‐crystallization from solution). In order to understand and control the formation of these pseudopolymorphic phases regarding potential uses, single crystals of the existing phases (two 1:2 and one 1:1 compound) were prepared, their structures were solved by single‐crystal x‐ray diffraction (XRD) analysis and the desolvation and phase transformations were studied using simultaneous thermogravimetry–differential scanning calorimetry (TG–DSC) and variable‐temperature powder XRD. The results explain the inclusion and desolvation behaviour and also clarify the observed, apparently accidental formation of a 1:1 or 1:2 inclusion compound at ambient temperature. Copyright © 2001 John Wiley & Sons, Ltd.