Specific interaction modes in the crystal structures of oligofluorinated tolanes featuring additional electron donor and acceptor groups
摘要:
A series of partially fluorinated and specifically para-substituted tolanes (1-4) have been synthesized via palladium-catalyzed Sonogashira cross-coupling reaction. The single-crystal structures have been determined by X-ray diffraction. The molecules adopt a geometry being more or less disturbed from planarity due to crystal packing effects. The packing structures are characterized by the formation of molecular stacks achieved through different modes of pi center dot center dot center dot pi interaction and being accomplished by other types of weak interactions including hydrogen bonds as well as bromo and in particular fluoro involved contacts. (C) 2011 Elsevier B.V. All rights reserved.