February 27, 2021, 01:13:58 PM
Forum Rules: Read This Before Posting

Topic: Electrophilic addition of Halogen and Water (Halohydrin) on Alkenes??  (Read 133 times)

0 Members and 1 Guest are viewing this topic.

Offline BioFelix

  • Very New Member
  • *
  • Posts: 1
  • Mole Snacks: +0/-0
I am currently learning for an organic chemistry test and I just couldn't come up with a solution to the following question:
Consider the reaction of 2-Propen + Br2 with water as solvent.
Why will the nucleophilic water molecule add on C-2 and rather than on C1 of the Bromonium-Ion?
The answer seems to be, because in the transition state the bonding between Br and C will dissociate quicker than the bonding between O and C will form, which leads to a positive charge on that C-Atom in the transition state and therefore water will add on the more stable "carbokation-like" carbon.
My question is: why does the Br-C bonding dissociate quicker than the O-C bonding forms? (I read that in the pearson organic chemistry textbook). Does it have anything to do with the Hammond-postulate? Or are there any other thermodynamic or kinetics reasons?
Unfortunately I haven't found an answer on the internet yet and also not in other textbooks.
Maybe you can help :) Thanks!

Sponsored Links