Triple helical structure constructed by covalent bondings: effective synthesis by a pre-organized partial structure and helicity induced by aromatic-aromatic interactions

Discotic helical macrocycle constructed by aromatic tertiary amide was effectively synthesized using dichlorotriphenylphosphorane as the condensation reagent. The yield was significantly higher when meta-substituted diaminobenzene was used as the linkage for a two 1,3,5-tris(4-carboxyphenyl)benzene moiety than when para-substituted diaminobenzene was used. The yield is thus dependent on whether the pre-organized partial diamide structure suits the construction of the macrocyclic structure. (c) 2007 Elsevier Ltd. All rights reserved.