Why is #Br_2# an electrophile?

1 Answer
anor277
Apr 15, 2016

Because the #Br-Br# bond is polarizable.

Explanation:

The halogen molecules have a large, polarizable electron cloud that (so we assume) can be distorted. #""^(delta+)X-X^(delta-)# representations are very common, and these explain the reaction of the halogens with electron rich olefin species.

Interhalogen species, say #I-Br# can also undergo electrophilic substitution. The iodine end of the molecule is more polarizable. The bromine is more electronegative. With an unsymmetrical alkene, say propylene, that reacts with 1 equiv #I-Br#, which alkyl halides would you predict you would get?

Related questions
See all questions in Introduction to Reactions and Mechanisms
Impact of this question
1382 views around the world
You can reuse this answer
Creative Commons License