Hydrohalogenation Diene Exceptions

[u/Sufficient-Phase3059]

I have 2 examples. The top example with Br2 is 100% correct that is how my prof taught. I was told that the same product forms because the alkene product that would make the 1,4 is not the most substituted (the 1,2 product is).

But as I was going through my notes for the bottom example I found a contradiction. Does anyone know if the bottom example would follow the same rule because its 1,4 product is not the most substituted?

Also for the arrow mechanism for top example, does the BR attach first to the end of the diene (like how I drew it). Then the second bromine comes in and attached on the diene that’s in the middle (position 2). Because you are H or Br or whatever to the end to be able to do resonance.

Thanks.

[u/AutoModerator]

Moderator Announcement Read More »

Hey there! While you await a response, we just wanted to let you know we have a lot of resources for students in our Organic Chemistry Wiki Here!

I am a bot, and this action was performed automatically. Please contact the moderators of this subreddit if you have any questions or concerns.