Experimental examination of transition-state structure

The concern for the possibility of generation of an ion pair that might be induced by the aqueous solvent system led to an examination of the solvolysis of 1,1-dideuterioallyl mesylate in an aqueous methanol solvent system. Here, however, no allylic rearrangement was observed in the formation of the substitution products thus, there was no rearrangement in the starting mesylate as well [47]  

It is important to note here that a deliberate attempt to generate an allyl cation-anion pair using a much more stable anion than an enolate ion led to no allylic rearrangement  

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