I. Csoregh et al., TRIARYLMETHANOL HOSTS AND ANALOGS .9. CRYSTALLINE ALCOHOLIC INCLUSIONS OF SINGLY-BRIDGED TRIARYLMETHANOL HOSTS - SYNTHESIS, X-RAY CRYSTAL-STRUCTURES AND BINDING MODES OF 5 INCLUSION-COMPOUNDS, Perkin transactions. 2, (2), 1994, pp. 303-308
Five alcoholic inclusion compounds of singly-bridged triarylmethanol h
osts have been synthesized and investigated by X-ray diffraction. In f
our cases recognition of the alcoholic guest by the host is characteri
zed by a coupled system of hydrogen bonds in the form of closed loops.
The centrosymmetric hydrogen-bonded rings, with full hydrogen bond sa
turation, are created by four -OH groups belonging to two host and two
guest molecules. in the fifth complex, however, 'anomalous' hydrogen-
bonded 2:1 host:guest associates are formed without full saturation of
hydrogen bonds. In the crystals the hydrogen-bonded units are held to
gether mostly by ordinary Van der Waals' forces, occasionally supporte
d by electrostatic C-H ... O interactions.