The alkene acts as a nucleophile, donating a pair of high-energy
pi-bonding electrons to bromine, Br2, to form a new C-Br
bond. In a concerted process, the bromine receiving electrons donates a
pair of electrons back to the other carbon of the alkene, and the
bromine-bromine bond is broken. This results in the formation of a
cyclic bromonium ion consisting of a three-membered ring with two new
C-Br bonds on the same face of the cyclohexane ring. The divalent
bromine atom in the ring has a positive charge.
|
Intermediate:
cyclohexene
|
