Helicoid Shiftamers for the Transport of -Clumps and Charges
نویسندگان
چکیده
Introduction. ± Sigmatropic shiftamers are (so far hypothetical) organic polymers in which localized electrons and/or atoms can be transported along the polymer chains by sequential sigmatropic shifts [1]. Recently, we described a shiftamer for the net transport of H-atoms along a polyacetylene chain via [1,7] shifts (Scheme 1) [1b]. We now show variants of this system that allow for the net transport of localized polyenes and polyenyl ions.
منابع مشابه
Helicoid shiftamers.
We report calculations on the activation barriers for antarafacial [1,7]-hydrogen shifts in various helical polyenes containing saturated substructures. Based on these calculations, we predict that the barrier for analogous hydrogen shifts in the infinite system-a [1,7]-shiftamer-is only approximately 14 kcal/mol if the reactant is preorganized in an appropriate helical conformation.
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