The Intramolecular Edge-to-Face Interactions of an Aryl CH Bond and of a Pyridine Nitrogen Lone-Pair with Aromatic and Fluoroaromatic Systems in Some [3,3]Metaparacyclophanes: A Combined Computational and NMR Study
Having the edge on aromatic–aromatic interactions: Model systems containing aromatic, fluoroaromatic, and heteroaromatic residues arranged in an edge‐to‐face disposition have been synthesized (see figure). Investigation of their structures and stereodynamic behavior shows a favorable interaction between an “edge” ring featuring a pyridine nitrogenlonepair and a perfluorinated “face” ring.
Six triple-layered [2.2]metaparacyclophanes have been prepared using general synthetic methods such as the Stevens rearrangement-Raney nickel desulfurization method, pyrolysis of bissulfone, and photo-induced desulfurization. The pyrolysis of bissulfone has turned out to be the most useful and convenient method for preparation of the intermediate double-layered [2.2]metaparacyclophanes because of simple experimental process and excellent yields. The unexpected formation of compound 9 during the photo-induced desulfurization of 7 was explained by a unique skeletal rearrangement of the intermediate 8 on irradiation.