Consider a functionalised molecular box or cage which has an electrostatic gradient due to positively charged groups one one of its faces. This environment is achiral as there are reflection symmetries

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Now place a chiral molecule which for example, has formal charges as shown

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Based on heuristic arguments on coloumbic repulsion, we expect the torsional potential energy surface of it and its enantiomer will look like this, where they will be mirror images of each other due to the rotational symmetry:enter image description here

Now suppose the gradient is something more general such as pH, concentration of a certain reactive species temperature and so on. Then we will suspect that despite they are enantiomers, the anisotropy of the environment will caused them to behave chemically different, with e.g. one of the more positively charged groups will became more reactive due to being positioned near the positive end of the electrostatic gradient of the environment.

  1. What is the terminology that refers to the difference in reactivity due to relative geometric arrangements of moeities between the molecule and its surrounding anisotropic achiral environment?

  2. Any good literature examples where this "rotational selectivity" is investigated or used in the context of chemical synthesis or molecular machines?


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