| Abstract
| - The synthesis and characterization of a series of azolium-linked cyclophanes are reported. Thecyclophanes consist of two azolium groups (17 examples) or three imidazolium groups (1 example)linked to two benzenoid units (benzene, naphthalene, p-xylene, mesitylene, 1,2,3,4- and 1,2,4,5-tetramethylbenzene, 2,6-pyridine, and p-tert-butylphenol) via methylene groups. Cyclophanescontaining ortho-, meta-, and para-substitution patterns in the benzenoid units were examined.The conformations of the cyclophanes were examined in solution by variable-temperature NMRstudies and in the solid state by crystallographic studies. The p-cyclophanes and mesitylene-basedm- and o/m-cyclophanes are rigid on the NMR time scale, as indicated by sharp 1H NMR spectraat all accessible temperatures. The non-mesitylene-based m-cyclophanes and the o-cyclophanesare fluxional on the NMR time scale at high temperatures, but in most cases, specific conformationscan be “frozen out” at low temperatures. Many structures deduced from solution studies wereconsistent with those in the solid state.
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