Conjugated compounds, and

Actually, this question focuses on the generation of a frozen transition state situation. Can each valence tautomeric equilibrium between an unconstrained cyclopropyl homo-conjugated compound and its open monocyclic counterpart be manipulated in such a way that a frozen transition state is obtained There are results pointing in this direction (see the following chapter3), however at the moment one is far from being able to generalize any of these observations. 

Initially this concept was developed to explain site-specific reactivities of conjugated compounds, and thus was confined to the jr-electron part of their electronic structure. The respective parameter was called superdelocalizability (Fukui et al., 1954,1957), and subsequently the approach was extended to saturated compounds, leading to the delocalizability as a generalized reactivity... 

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