Give the expected products of the following acid-catalyzed rea...

Question

Give the expected products of the following acid-catalyzed reactions.

(a) acetophenone + methylamine

Accepted Answer

All right. Hi everyone. So for this question we must determine the expected product of the acid catalyzed reaction between um propio phenomenon and fennel method to me. So let's begin, first of all by recalling the fact that we have a primary amine, like our fennel method, I mean here and we react our primary amine with a ketone or an alga hide in acidic conditions. That's going to generate what we call an I mean, and I mean look very similar to car bottles, but we're going to have a C double bond N instead of a C double one. Oh, so in order to start off our reaction, let's go ahead and draw out our starting material are propio um, fennel. So we're gonna have a Benzene ring here and we're going to have our carbonnel followed by an ethyl group. So this is gonna be our starting keto. And recall that our first step um is going to be the proto nation of our ketone by a free floating proton. Right? Because we are in acidic conditions. So that's going to generate a pro donated ketone. We're going to have a positive charge on our oxygen. So this is our now oh, age. And that's going to have a positive charge on oxygen. So now that oxygen of the carbonnel has um has a positive charge. This is where our fennel method amine is going to come in, Right? So we have a primary amine, like I mentioned before, and we're going to have one carbon connected to a benzene ring. So the lone pair of electrons on nitrogen is going to go ahead and attack the carbon of our car bottle and of course that's going to push the pi electrons over carbonnel upwards um towards oxygen. So that's going to generate a neutral oxygen. And we're going to have our tetra hydro um intermediate. So this is our final group. And now, like I mentioned before, we're going to have, well this is our ethyl group and now we're going to have a neutral oxygen. Right? We're going to have an O. H group, but because the nitrogen of our Amin has connected um to the carbon of our car bottle, that's going to give it a positive charge. So we're going to have a positive charge on nitrogen, which is not ideal. Right? So this is where our proton transfer is going to come in because what's going to happen here is that one of the hydrogen of our mean is going to donate its electrons towards nitrogen and it's gonna essentially detach itself. So, from this point forward, we do have equilibrium arrows. So just be aware of that fact. And now we're going to have another free floating proton because of this proton transfer. Right, so we are in fact going to have a neutral nitrogen this time and now we have a free floating proton. So because we have a free floating proton. Now, then the O. H group, that was our car bottle. That's going to go ahead and get protein ated. Right, because recall that, ohh by itself is not a good leaving group. So after proto nation, it becomes an O. H two plus, which is a fantastic leaving group because that is simply going to detach itself as water. So in our next step, in our next step, we're going to have an O. H two plus, like I mentioned before and that is going to be a fantastic leaving group. So this is going to be our OH two plus and this is going to be our nitrogen which is still neutral of our mean. Alright, so now, So now, like I mentioned before, ROH two plus is a fantastic leaving group. So that's going to leave. And once that leaves, the lone pair of our nitrogen is actually going to jump in between itself and the carbon it is attached to. So once again, we're going to have a positively charged nitrogen but we're going to have a double wand this time um in between itself and the carbon is attached to, right? So we're going to have this is our ethyl group and now we're going to have a double bond in between nitrogen and carbon with the hydrogen still attached to nitrogen and of course our our group giving that a positive charge. So in order to get rid of the positive charge on the nitrogen, our proton here of our mean is going to go ahead and detach itself like the first one did during our proton transfer. Right? So that's gonna go ahead and detach itself and donate um its electrons towards our nitrogen to make it neutral once again. So at the very very end of this process, we're going to have our ethyl group, we're going to have a double bond in between nitrogen still but our nitrogen is going to be neutral, right? Because a pair of electrons was donated towards it by um by that proton. So this is going to be our final answer, right? This is going to be our I mean because notice that we have that C. Double one N. And that is going to be it for this question. So let me just scroll up to the top so you can see what we did. And the answer to this question is going to be choice C. So with that being said, thank you so much for watching and I hope you found this helpful

Give the expected products of the following acid-catalyzed reactions.
(a) acetophenone + methylamine

Key Concepts

Acid-Catalyzed Reactions

Nucleophilic Addition

Imine Formation

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