Features of this migration

• • The carbocation may be produced by a variety of ways.

• Hydrogen can also migrate in this system.



• Aryl groups have a greater migratory aptitude than alkyl group or hydrogen due to the formation of lower-energy bridged phenonium ion.



• Rearrangements in bicyclic systems are common.



• The rearrangement is stereosepecific

• Two or more rearrangements may take place simultaneously.

Examples: