SYNTHESIS, MOLECULAR STRUCTURE, AND OXIDATION BEHAVIOR OF EXHAUSTIVELY METHYLATED AZACALIX[6]ARENE

摘要

The molecular structure and oxidation behavior of an exhaustively methylated azacalix[6]arene have been investigated with the intention of developing high-spin materials. The azacalix[6]arene adopted a distorted 1,3-alternate conformation in the solid state, whereas the conformation was highly flexible in solution at ambient temperature. As a result of the flexible structure in solution, the decreased stability of the corresponding cation radicals was observed, as compared to that of the smaller inflexible homologue yielding stable cation radicals. Both the conformational inflexibility and the steric protection of reactive sites were found to be crucial for stabilizing the oxidized species of this molecular system.