 it's true there's a lot of haters out there anyways you guys hopefully remember this mechanism from organic one right so this is the Markovnikov edition of HBR to an alkene okay so you can see the reactants you can see the products notice that the bromine went to the more substituted side of the alkene right and the hydrogen went to the less substituted side that is Markovnikov addition to the alkene where the hydrogen goes to the less substituted side and remember why it's because the carbocation that's formed is more stable if it's more substituted so let's just go over the mechanism because I'm sure that some of you guys have forgotten when HBR is in the presence of an alkene there these electrons here will deproven a very acidic right very acidic so this thing acts as a base okay so it's got a choice as to put the proton on this side or on this right so those choices would give us two different carbocation so we put the proton here we give us that primary carbocation if we put the proton here right it would give us the tertiary carbocation right well it's the only one that it's going to do this will not happen that won't happen because primaries don't form so you got to do you got to push the reaction real hard to make a primary carbocation so anyways since we know that's not gonna happen the tertiary is going to form so what's going to happen is that these electrons here are going to deproven a VR like that and in fact let's just go ahead and go through that caravan just to emphasize it okay and then when that happens we get that as an intermediate plus of course VR much less match made in heaven and of course remember this is sp2 hybridized right so it's trickle planar so this attack can come from the bottom or the top okay so if we were making if these were two different groups here we would be making a stereo center but since they're not we're not going so that is what we expected turt butyl bromide and again remember so this is Markovnikov addition of HBR to an alkene so we can do also anti Markovnikov addition of HBR to an alkene but we need an initiator okay and because why because it's a radical reaction and we're going to show that next okay so these are going to be effectively reactions that you can use in opposite situations one if you want the Markovnikov addition the other one if you want the anti Markovnikov okay everybody okay with that any questions on this one pretty straightforward you guys have known this one for a long time