An intramolecular reaction of 3-alkynyl and 3-alkenyl-2-arylpyridines selectively gave 4-azafluorene compounds in the presence of a catalytic amount of [Cp*RhCl(2)](2) and Cu(OAc)(2). Pyridine-directed C-H bond activation along with "rollover" are likely to be key steps of this transformation.
Several aromatic bridged cryptophanes were successfully synthesized. p-Xylene bridged cryptophane Anti-3 was prepared by the direct trimerization of ci,ci'-bis[4-hydroxyme thyl-2-methoxyphenoxy]-p-xylene. The synthesis of o-xylene bridged cryptophane Anti4 was carried out by the direct trimerization and/or the stepwise method from vanillyl alcohol. The 0-[4,5-bis-(methoxycarbonyl)]xylene bridged cryptophanes Anti-15a and Syn-15b were also prepared by the stepwise method from vanillyl alcohol. Anti-3 was capable of complexing with almost all the quaternary alkylammonium cations among the primary, secondary, tertiary and quaternary ammonium cations, and selectively prefered to complex with the NEt,Me+ cation as a guest. From the complexation of the o-xylene bridged cryptophanes Anti-8, and the analogs Anti15a and Syn-15b with the NMe,+ cation, the cryptophanes Anti-8 and Syn-15b were confirmed to complex with the guest cation, however, Anti-15a was not confirmed to be included.
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