Predict the major products of the following reactions:
...

Question

Predict the major products of the following reactions:

(b)

Accepted Answer

Hey everyone and welcome back draw the major products expected from the reaction shown below our starting material is a key tone. And we're using two reactions number one, we are adding hydrazine, number two additional potassium hydroxide and the presence of heat, we may essentially recall that this reaction is called the Wolf Kushner reaction. Or to be more specific reduction. Right, Okay. So let's remember how this reaction takes place. The mechanism might seem a bit lengthy, but no worries. It's not too difficult. So we will just look at the mechanism to see the steps supporting our answer. So we may simply begin by drawing our key tone. That's our starting material. And in the world, first step, we have the attack by the lone pair of nitrogen within hydrazine. So we're going to draw that nitrogen nitrogen bond, there will be NH two group on the right hand side, on the left hand side, we have another NH two. And now the lone pair on nitrogen would essentially attack the electra Philip position within the carbon steel. And we're breaking our pi bon. So, this is our first step. We may simply draw the expected structure. Now, if we look at this one, we simply understand that we are breaking our pi bond, right? So we are going to get oxygen with a formal negative charge right? And that we are going to bond our nitrogen to this carbon nitrogen would still have two hydrogen atoms and then it has bonded to another NH to this nitrogen would have a formal positive charge because it has four bonds. And essentially, we want to first of all the protein it that nitrogen notice how we are using potassium hydroxide. So that base would allow us to perform that deep proto nations. We can actually expand these hydrogen and we can show that we have won hae jin and the other. Now the incoming base O H minus would allow us to achieve that deep protein nation. So we are going to try the resultant and immediate. Okay, and now, if we essentially think about the intermediate, we're going to get rid of that nitrogen hydrogen bond. And from here we are just going to protein eight oxygen. We have formed water and the molecule of water will act as a proton donor. Now the negative charge and oxygen would essentially attack the proton. We would reform our O H minus. And from here we are getting our next structure. So let's draw it out. We already understand that we are going to have oxygen wanted to hydrogen. So we're getting our alcohol group here. Okay, well done. Now in the next step of this mechanism, we are going to use a lone pair of nitrogen which will allow us to form the pi bond because we can now get rid of the leaving group which is O. H minus. So we're going to form a pi bond at this position, we are going to get rid of our alcohol group from the fragment and then let's see what we get from here That would correspond to the following structure, leads added and let's fix it. So this is our previously drawn structure. We are essentially going to get rid of that O. H. And we may simply draw that Now at this second position we will have nitrogen that is double bonded two Carbon. So that be nitrogen where hydrogen and it has an N. H. T substitution. So let's add that amino group. But now because this Nigerian still has four bonds, we're going to have a formal positive charge on it. And in the world final step here we just want to remove that proton and produce our hydro zone intermediate. So we're going to expand that nitrogen hydrogen bond and we are going to use the base previously formed that will allow us to achieve that transformation. We will just be protein ate that and get the following structure. Okay, now let's remove that hydrogen because we have the protein ated nitrogen and now nitrogen will only have three bonds with a lone pair. Right, we're essentially forming a lone pair of nitrogen. So we don't have any formal charge anymore. And essentially this is our hydro zone intermediate. Now also let's add that reaction arrow. So we can clearly see that this is our next step. And from here we have to think of our next steps and for that purpose we are just going to expand one of the hydrogen atoms bonded to the other nitrogen that would be an age. And then another Haijun. We're going to use another equivalent of our base O. H minus which is going to capture this proton. Then we are going to transfer these electrons into that nitrogen nitrogen pi bon and break the adjacent pi bond by transferring the electrons onto carbon. From here we can throw our next intermediate which looks like this so we can throw our chain. Now we have single bond over here but we have our negative charge on that carbon nitrogen has wanted to another nitrogen via a double bond and now we have an age. Now this carbon can get protein aided by the water molecule present in our solution. We have previously formed a water molecule. So you can show that the negative charge that tax and we are adding our first proton over here also, let's add that little group. And now we can clearly see that we end up with nitrogen nitrogen double bond and we have our hae jin from here, We just repeat the previous step. We're going to expand at night in hydrogen bond. So let's try it. And essentially we're going to use our base, take that proton transfer these electrons into a triple bond now and then transfer these nitrogen carbon electrons two carbon in the form of a lone pair. Notice how we're forming nitrogen gas here. Okay, so we get our carbon ion which looks as follows. So we have our negative charge in this position, there's a lone pair, we have our Nigerian gas as a byproduct. Let's keep that in mind. That's one of the features of the Wolf Commissioner reduction. And finally, because we have that negative charge, we're just going to use another equivalent of water, right? We're going to perform the protein nation step and get our L CAin. Right. So we have successfully performed that reduction and we can show the final product from here. Okay, well done. We have added our two hydrogen atoms. That's it. The mechanism was a bit lenzi it might be difficult to understand. So let's just summarize our findings and let's add the product. So whenever you see this set of regions for the Wolf Kitchener reduction, you essentially want to understand that you're going to replace your carbonate group with two hydrogen is and that's it. So if you don't want to understand that much about the mechanism, you can skip that step and you can just think about the Wolf Kitchener reduction as an exchange of that carbonell group with within a key tone with two hydrogen atoms. So the product that we get here corresponds to the following chain of carbon atoms. And then instead of drawing that carbon here, we will just have to implicit hye jin's there's no necessity to expand them. Now let's label this structure is our final answer and based on the product that we got, we may conclude that the correct answer to the multiple choice question is the. However, If you have any questions, don't hesitate. Slavery, comment down below. Thank you for watching.

Predict the major products of the following reactions:
(b)

Key Concepts

Wolff-Kishner Reduction

Hydrazine and its Role

Base-Catalyzed Decomposition

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