Heteroaggregation between Isomeric Amido-ethynyl-amidohelicene Tridomain Oligomers

摘要

Three isomers, i.e., P4M5P4-1, M4P5M4-1, andnM4M5M4-1, of amido-ethynyl-amidohelicene tridomain oligomersnwere synthesized. P4M5P4-1 formed four homoaggregate states, i.e.,nall-dimer, amido-dimer, ethynyl-dimer, and random-coil states, bynindependent aggregation and disaggregation at the ethynyl andnamido domains. Then, possible combinations of heteroaggregationnwere examined between the isomeric tridomain oligomers P4P5P4-1,nP4M5P4-1, M4P5M4-1, and M4M5M4-1. When P4P5P4-1 andnP4M5P4-1 were mixed in THF, to which trifluoromethylbenzenenwas added, heteroaggregates with an all-dimer structure were formednwithout forming homoaggregates. The heteroaggregation initiallynoccurred at the central ethynyl domain, which was followed by thenaggregation at the amido domains. Heteroaggregates were also formednusing the combinations P4P5P4-1/M4M5M4-1 and P4M5P4-1/M4P5M4-1, and the results indicated an important role for thencentral ethynyl domain for heteroaggregation.