Solid state conformations of symmetrical aromatic biheterocycles: an X-ray crystallographic investigation

CM Fitchett, C Richardson, PJ Steel

Index: Fitchett, Christopher M.; Richardson, Chris; Steel, Peter J. Organic and Biomolecular Chemistry, 2005 , vol. 3, # 3 p. 498 - 502

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Citation Number: 33

Abstract

Accurate, low temperature X-ray crystal structure determinations show that 3, 3′- biquinoline (6), 2, 2′-biquinazoline (7), 2, 2′-biquinoxaline (8), 2, 2′-bibenzoxazole (10) and 2, 2′-bibenzothiazole (11) all exist in the solid state in centrosymmetric, planar conformations that minimise their dipole moments and maximise both conjugation between the rings and various types of attractive intermolecular associations. In contrast, 4, 4′- ...