Synthesis of multilayered [3.3](3,5)pyridinophanes

Two- to four-layered [3.3](3,5)pyridinophanes (PyPs) have been synthesized by the (4-tolylsulfonyl)methyl isocyanide (TosMIC) method. The coupling reaction between 3,5-bis[2-iso-cyano-2-(4-tolylsulfonyl)ethyl]pyridine (TosMIC adduct) and bis(chloromethyl) or tetrakis(bromomethyl) compounds in the presence of sodium hydride in N,N-dimethylformamide or sodium hydroxide and tetrabutylammonium iodide under high-dilution conditions gave the two-layered dione or three- and four-layered tetraones. Wolff-Kishner reduction of the ketones afforded the desired two- to four-layered [3.3](3,5)PyPs. The structure of the dione units take an anti geometry whereas the cyclophane units take a syn geometry in solution.