| Abstract
| - The synthesis is described of the first helical ladder polymerswith unbroken pathways of conjugationthat extend not only through each monomeric unit, but between them aswell. The key step is thecondensation of 1,2-phenylenediamine and a transition metal salt with ahelicene havingsalicylaldehyde's functionality at both ends. This gives rise to“metal salophen” units that bindadjacent helicenes, provide conjugated links from one ring system tothe next, and constrain thep-orbitals of the rings they unite to be nearly parallel. Becausethe helicene monomers areenantiopure, so too are the polymeric structures to which they giverise. One of the polymers (6)winds continuously in only one direction. Another (4a)winds in one direction through the helicenemoieties and in the other direction through the metal−salophens.The circular dichroisms of theformer at wavelengths near 600 nm are notably large. Thecorresponding circular dichroisms ofthe latter are much smaller. MALDI-TOF mass spectra provideparticularly strong evidence forthe structures assigned. The polymers are very soluble in avariety of organic solvents and seemto have number average molecular weights of ca. 7000.
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