TRIARYLMETHANOL HOSTS AND ANALOGS .8. CLATHRATE DESIGN FOR DIOXANE INCLUSION INVOLVING SINGLY BRIDGED TRIARYLMETHANOL HOSTS - SYNTHESIS, X-RAY CRYSTAL-STRUCTURES AND THERMAL STABILITIES OF 5 INCLUSION-COMPOUNDS

A series of singly bridged triarylmethanols, with different substituents and modified bridging units, form crystalline inclusion compounds with dioxane. X-ray diffraction studies revealed hydrogen bonds between host and guest in all these structures, and in one case also a host-to-host hydrogen bond. Most crystals contain either 1:1 or 2:1 hydrogen-bonded host-dioxane complexes, dependent on the structural parameters of the host molecule. With both host-guest and host-host hydrogen bonds present, 4:1 host-dioxane units are formed. Some structures accommodate additional dioxane guests which are held by van der Waals forces. The stabilities of the different dioxane clathrates were studied by thermal analysis.