00:01
This problem asks us to draw the mechanism for this reaction.
00:05
So first we'll figure out what mechanism we're drawing.
00:08
So we end up with an alken here, and we have a weak base weak nucleophile.
00:13
So this will be an e1 reaction.
00:16
So the first step in an e1 is to kick off the sleeping group to get a carbocation.
00:20
So that first carbocadion intermediate will look like this.
00:29
This will be our carbocation.
00:31
And you'll notice that we start off with a four -membered ring and we end with a five -membered ring and that's because a five -membered ring is much more stable than a four -membered ring.
00:41
So while we have this carbocation, the electrons in this bond right here will come over and grab the carbocation and make a five -membered ring.
00:49
So that intermediate will look like this.
00:52
So if we number these, one, two, three, we'll say one, two, three, this will be four, and this will be five.
01:00
Five ends up between three and four...