Argento cationic intermediates

Strained cyclic systems such as cyclopropane derivatives proved sensitive to silver ions. Indeed, silver usually induced ring opening of cyclopropanes, leading to argento cationic intermediates, which evolved further depending on substituents. Most, if not all, of these ring rearrangements resulted from initial formation of a a complex of the cyclopropane with silver ion. 

It is worth noting that both secondary argento cation intermediates could be in equilibrium through either an H or vinyl shift, depending on the nature of the R1 group (Scheme 3.12). 

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