00:01
In this problem, we are talking about the mechanisms and predicting the products of alkeny reactions.
00:08
Specifically, in this case, we are going to be reacting alkenes with halogens.
00:15
And that's what we're going to be going over today.
00:17
And we're also going to be using stereochemistry.
00:21
So for part a, we have this cyclic structure that has an alken and we are reacting it with diatomic bromine.
00:28
Remember that our mechanism arrows always go from electron rich to electron pore.
00:34
This is the idea of a polar reaction using an electrophile and a nucleophile.
00:41
So we're going to have this double bond that's electron rich, going to our bromine and picking up one of the bromines.
00:49
And then we, pardon me, we will return our two electrons of this diatomic bromine bond onto one of our bromines.
00:56
So now we are going to form this ring that has essentially an epoxide with this bromine atom.
01:06
And then we have a leftover negatively charged bromine anion.
01:11
So these electrons are going to attack our epoxide ring and open it up.
01:17
And this would be our product.
01:19
We have this ring here.
01:21
We have a trans relationship between our bromine atoms where one would be pointing above the plane, one would be below, and that would be our product for our first reaction.
01:32
Now for our second reaction, we have something very similar, but now our alkenes is not internal, it is a terminal alken, so we're going to have a terminal epoxide.
01:44
So again, we have this benzene ring attached to this alken and we are reacting it with diatomic chlorine.
01:50
So again, we go for electron rich to electron poor.
01:54
Our double bond is going to pick up one of these chlorine atoms and return the two electrons onto our chlorine.
02:00
That's how we're getting an anion...