Aryl- and Alkylarylmethyl Cations

The first stable long-lived carbocation observed was the triphenylmethyl cation108 110 47. 

Because of the high stability of the tertiary ions, these are preferentially formed in the strong acid systems from both tertiary, secondary, and even primary precursors115.  

however, the tertiary carbocation is not benzylic, rearrangement to a secondary, benzylic ion can be observed  

With suitable substituent groups (which also prevent transalkylations) secondary styryl cations were found as stable, long-lived ions116,1,7  

Although the unsubstituted benzyl cation is still elusive, many substituted derivatives have been observed116  

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