Semi - Empirical Study of a pH - Switchable [ 2 ] Rotaxane
نویسنده
چکیده
Semi-empirical (AM1) electronic structure calculations are reported on a pH-switchable [2] rotaxane whose synthesis was reported in [Angew. Chem. Int. Ed., 36 (1997) 1904]. The [2] rotaxane possesses two cationic binding sites, with different affinities toward dibenzo [24] crown-8 (the ring component of the [2] rotaxane) depending upon the pH of the system. The computational results capture this pH-sensitive bistability, the key device-like characteristic of the rotaxane.
منابع مشابه
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Synthetic catalysts have previously been developed where a stimulus can be used to turn the catalytic activity ‘on’ or ‘off’ or to change the stereochemical outcome of a reaction. Here we report on an articial system that can switch between two different modes of organocatalysis, each promoting a different chemical transformation. The result is a molecular catalyst that can be used to produce ...
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