 When this substrate is subjected to E1 conditions, will a carbocation rearrangement occur? That's the question, okay? So how do we figure that out? What's the first thing we need to figure out? If we're going to see a carbocation rearrangement occur, we have to know what. We'll make it a carbocation. Make it a carbocation. So let's figure out what the structure of the initial carbocation intermediate would be. Okay, so E1 conditions, if you guys recall, for an alcohol we've shown H2SO4 and heat, if you want to say. Okay, so what kind of carbocation? What would be the carbocation that I would get from that? Secondary. Yeah, the secondary and the positive charge would be what? Right where the OH. Yeah, where the hydroxyl group is. Okay, so what did we say, a secondary carbocation? Is that the most stable carbocation we could have? You can do a methyl shift and make it a tertiary. Yeah, so no, it's not the most stable. We could make a tertiary, which would be more stable. How do we make a tertiary? Well, we have to do a methyl shift in this particular case. Remember, these things are methyl groups. Okay, so in order to do a methyl shift, we would do a 1-2 methyl shift, that's what we're about to do. Carbocations will do these 1-2 alkyl shifts or 1-2 hydride shifts if they can make a more stable one. So, if we can go from a secondary to a tertiary, it will. That methyl group there, doing that 1-2 shift, and our other methyl group stays put, our positive charge moves to that carbon there, the carbon alpha to the initial positive charge. And we now have a tertiary carbocation, which is more stable than the secondary carbocation. Can it shift like an ethyl group or a methyl group? Yeah, so yeah, you can shift an ethyl group, you can shift bigger groups, yeah. It's generally called a 1-2 alkyl shift. Probably most of the time in your examples you'll see the methyl shift the most. Also remember the hydride shift too, we've done a couple of the problems on it. Any questions on this one? So again, I'm not going all the way to the products here, this is just to the intermediates to see if it's shifted. Any questions on this one?