Nitrogen-bridged macrocycles: synthesis, structures and inclusion phenomena

摘要: Abstract Synthetic methods of nitrogen-bridged macrocyche best molecules such as highly symmetrical cage compounds 3 6 and their bond isomers 8, 10 , azacalix [ n ]atenes 16, 18 20 tetraaza[3 4 ]cyclophanes 24 31 are summarized. The new class macrocycles 3–6 were designed synthesized by one-step coupling reactions. In the compounds, pyridine or benzene units connected four bridgehead nitrogens, both nitrogen lone pairs directed into cavity. inversion is inhibited rigid structure. Because tthe preorganized structure 5 with six donors, respectively, they strongly bind alkali metal ammonium ions, exemplified fact that obtained K + complexes in compound showed Rb selectivity among its complex was confirmed X-ray structural analysis. hosts also form very stable proton cryptates (H ∋ ·OH − H ). They relatively stable, but slowly changed water 2 O∋ Oχ cation affinity host can be controlled attaching electron-donating -withdrawing substituents on rings. A Cl ion formed acidic solution, Br I other anions larger than could not encapsulated . azacalixarenes, a family calix[ ]arenes, have more corresponding oxacalix[ ]arenes because strong intramolecular hydrogen bonds between phenolic hydroxyl groups pairs.