We've got 2 transformations that we need to keep track of here. First, I need to turn my tertiary amine, which would be referred to as an aniline derivative because this is an aniline with 2 R groups, so it's an aniline derivative. Somehow I need to turn my tertiary amine into a quaternary amine. You might have a better idea of how to do that now that we just went through this reaction. We'll be giving you some ideas. Have you seen a quaternary amine being made before? Another transformation that I need to make is I need to add chlorine to the meta position of the benzene because it's meta to the original group that was there. We've got basically 2 reactions that need to happen. One of them is going to have to be an amine alkylation because amine alkylations are a really surefire way to get quaternary amines. Once you have a quaternary, you can't keep alkylating, so that's the endpoint. That's actually going to be the perfect reaction for this.
Now over here, to add the chlorine, that's going to be an EAS halogenation or an EAS chlorination. Now the question is, does it matter which order these are in, or can I just put them in any order? The order matters, guys, because right now, this is an ortho/para director. Aniline derivatives are ortho/para directors. They're one of the strongest ones there is. Whereas notice my quaternary amine has what kind of charge? Positive. Do you guys remember what a positively charged substituent is going to do? It's going to be a deactivator. It's going to be a withdrawing group. This is now an electron-withdrawing group. It's actually one of the strongest electron-withdrawing groups because it has a full positive charge right there and it's going to be a meta director. What that shows you guys is that amine alkylation is actually a sequence group. Again, this is all drawing from your aromaticity section. But just letting you guys know, it is a sequence group because this group can alter the sequence of the reagents for synthesis. In this case, since I want meta activity, I want a meta-directed product, I'm going to go ahead and do my alkylation first. The specific R group I'm adding is just the CH3, so I could just use a methyl alkyl halide. I'm going to use CH3Cl. Normally, we would run an amine alkylation in base, so I would say CH3Cl and NaOH. But there's not going to be anything to deprotonate here because I'm literally just adding the 4th R group on. That's all I need. I don't need a base here. In fact, if I put in a base, it's not going to do anything. There's nothing to deprotonate. You would only use a base if you were starting from a primary or secondary or ammonia. If you're starting from a tertiary like this, then there's really going to be nothing to deprotonate.
Now the second reaction is going to be the EAS halogenation. You guys remember the reagents for that? You got this. Cl2 and FeCl3 as my Lewis acid catalyst. That is going to make my chlorine atom in the meta position because now I have a strong meta director and we're good. I hope that made sense, guys. This is really the only synthetically useful application of amine alkylation. We're not going to use it a lot for synthesis because of the complications that we just discussed with polyalkylation. Let's move on to the next reaction.