 So, what we have discussed that in astring medium, we will try to get more stable alkene, more stable alkene, write down the possible product and then you compare the stability of alkene, the one which is more stable is a major product. Now, you see basic medium mechanism. Basic medium, I will take the same example. Basic medium is this OH minus will happen. Now, this basic medium takes H plus in the first step, this attacks over here and it takes H plus from the first step, this electron pair comes up to this carbon. So, the product here we get is intermediate non product CSP C double bond O CH2 with lone pair on carbon and negative H2 plus H2. Is it clear? Base, acid base reaction. Now, this step is the RDS of the reaction. Slowest step RDS. You should know this. RDS is what? Formation of carbonyl. Formation of carbonyl. So, we try to get stable carbonyl. If more than one carbonyl is forming, then the carbonyl which is more stable gives you the major product in this. So, more stable carbonyl will form. Now, in the next step, first step of the reaction is this. In the next step, this carbonyl CS3, one thing also we can write here. We can write down the resonating structure here because lone pair sigma of pi bond, this comes over here and this goes over here. So, this will have CS3 CO minus double bond CS2. Now, this one CS3 CO minus double bond CS2 in the next step takes H plus from the water molecule which forms in the first step, this water molecule. Because, base is again, it is what? It is catalyst. So, it won't get consumed in the reaction. Eventually, it has to come out as OH minus. The concentration of base is not changing. So, when this O minus takes this H plus, then OH minus goes out and we end up getting what? CS3 COH double bond CS2 plus OH minus. So, isn't it the same mix? Yes. Yes. So, point A is that the mechanism is different. For example, if you can't ask for this. If you can't ask for this. If you can't ask for this. If you can't ask for this in JEE, competitive example. How would they ask for this? Mechanism they won't ask. Now, the question is that you would understand what is the advantage of this mechanism. Okay. You should know this that in basic medium, carbonyl you have to concentrate on. You should get the only way to find out the RDS is experimental. You should know this. This information is given in the book. Is it possible that the most stable carbonyl doesn't form the most stable alkyne? No. It's not possible. Most stable always gives you major product and most stable alkyne. But here we don't call that will form more stable alkyne. Because this step in which the alkyne is forming is not the RDS of the reaction. RDS is this. So, we talk about most stable carbonyl not alkyne. There was a product that we are getting here and in acetic medium is same. But the mechanism is different. Suppose if I write down this one, one example I will give you, which we have already done. But in basic medium we will see. So, one note you write down in this first. In basic medium we will try to form, in basic medium we will try to form most stable carbonyl first, which gives the major product. This example we have already done. Tell me the major product in this. The mechanism is basic medium. The medium is basic, basic medium. Major product in this one. Same product we are getting. Major product equals only one product. It will be the opposite. Major will be one, yes. So, there is only one product. No, there are two products. No, there will be two products. There will be two carbonyl. Carbon and that carbon is the hydrogen. We get these two products. Which one is more stable? Second. Second one. Where is four? Six. I have given you the product so we form to this path. So you have to see in those products what are the carbonyl forming. And then what is the hydrogen? Alfa hydrogen won't work here. No, it won't work here. It's not actually, it's this. You try to understand one thing. Just take what's in the first step. What's happening in the first step? OH-minus takes H plus from alpha position. So here, the base here, this will take H plus from the alpha position. Now we look to alpha position. This is the stable position. So when this H plus comes out, we'll get carbon ion here. That is 2TD carbon ion. So which one is more stable? This one is more stable. This gives you the main product. So this will be the major one. I want you to write down the mechanism. This mechanism, we write down for this question. At this mechanism for one question. So here, hydrogen for the carbon which are bonded to the carbon bond. Yes. So here, hydrogen for the carbon which are bonded to the carbon bond of all this. Yes. Yes, yes. Sir, but alpha is a major product should be same in both of them. What are you saying? Are we getting a very good one? Sir, can we just find which has more, lesser alpha particles and say it's that? No, you don't know that. Alpha is a particle. Alpha, I know that. Yes. See, what I will tell you? I will tell you. You just have to form the more stable carbon ion. You can talk in other way also. The carbon which has more number of hydrogen. Right. That gives you more stable carbon ion because there will be no plus side effect. Okay. Now, stability of carbon ion for that you have to apply all those concepts of GOC. GOC whatever you understand. In any chemistry, everything is connected. We will get confused. Okay. Did you write down the mechanism of this one? Right. Two different carbon ions that we get here is when hydrogen comes out from this carbon and hydrogen comes out from this carbon. I will just write down the carbon ion here double bond O with negative charge plus here we have negative charge and double bond O. This is 2 degree carbon ion so which one is more stable? One degree carbon ion is more stable. One degree, two degree and then three degree. In case of carbocation that stability order is because of plus high effect or plus H also you can say. Okay. But in carbon ion, hyperconjugation is not possible. Carbon ion may hyperconjugation is not possible. It is only possible in theoretical. Carbocation and alky. So, this gives you the major product. So, major is this one. Okay. Can it be the major and minor product in this? Immediate is basic. First of all you write down the product. The two product that you get and then you think which one is more stable. One degree and three degree. One degree and three degree. One degree and three degree. Two degree and three degree. See. We will get a carbon ion. We will get a carbon ion here and we will get a carbon ion here and the two carbon ions we will get. This is three degree and this is two degree. This one is more stable carbon ion. This gives you the major product. This comes over here. This biorecton strip over here. H attached under this oxygen. O H. This is the two product we get. Which one is major? The first one is major. In ascetic medium what was the major product in this? The second one. Opposite, right? So, what we can say the major product in ascetic medium becomes minor in basic medium. Can you see that? It's always. It's always. We always. Always. Always. So, whatever we have discussed so far that major in ascetic becomes minor in basic. This question you say? Exception. Write down the product in basic medium and acetic medium. No. Basic. So, I mean the product should be same with the major minor product. No. Where? Such a big component. In ascetic medium. Also such a benzene. Benzene gas. It's very difficult. It's very difficult in benzene. Benzoic acid. Also something has to be benzene. No. Done. What is the product we will get here? Major product, basic medium? One. And here the major is? Opposite, right? Very great. No. No, sir. Look. Yeah, I don't see anything. Which one is the major? Which one? See, first of all, we will write out the product here. Oh yes, sir. It will be opposite. Now you listen to me. Acetic medium. We will write out alkene directly. Because we have to compare the stability of alkene. The alkene that we get here is double bond here. Yeah. And double bond O. O H. This one product. And other product is this. Yeah. Here the product is? What happened with this one? In this one, in this one, what we have to do? We have to compare the stability of? Acetic medium. Alkene. Acetic medium, alkene. Side effects. Number of alpha hydrogen. How many alpha hydrogen we have here? Three. Three right, sir? Yes. Which one is more substituted? Four. Here you see, one hydrogen is substituted with O H. And here one hydrogen is substituted with N O 2 O H. So which one is more substituted? The first one. The first one, right? This alkene is more substituted. This is more. Sir, also it has more alpha hydrogen. It also has more alpha hydrogen. Number of alpha hydrogen is two here and two here. Four. Then two plus one there. And here it is? No, it's not four. Two plus one. Three. Two plus alpha hydrogen. This is the answer. This is one thing. Second thing is what? This is in resonance. This is in resonance with this, right? So lone pairs, sigma pi, sigma pi resonance. That's why this is more stable. Alpha hydrogen is also more substituted. So this one is more stable. Since the medium is acidic, so we'll write down the alkene and we'll compare the stability of alkene. But basic medium, the intermediate is what? The intermediate is? Carbonide. Carbonide. So here we won't write the product directly, but it will write down the carbonide that forms in this reaction. Can we get a carbonide here? This one is the same thing. And here we'll get the negative charge, double bond O. Now which negative charge is more stable here? First one. Why first one? Because this group shows here minus M effect. Here we do not have such effect on this negative charge. So this is more stable. This gives you a major product. So the major product is what? This is the major product. So is there any resonance also of sigma pi, sigma lobe? We are talking about the stability of the negative charge. So we'll see this in conjugation with this. There's no conjugation here. This conjugation is here. It's on the right or on the left side? We have here. Here we have this side and this one. Minus M effect. The negative charge is the range. This applies by the minus M nature of this. But here we do not have minus M nature. What's the difference between dancing resonance and auto-minus M? Dancing resonance is only possible in cyclopropyl ring first of all. And there is no change in the position of attitude. It's only cyclopropyl. Just cyclopropyl. Just cyclopropyl. And there's no change in the position of attitude. Electron pair is the same. Because cyclopropyl is stable. Because cyclopropyl is stable. The angular state is very high. That's right. So that is why in acidic medium we are getting major product risk. Basic medium also the major product. So it is not like the major product in acidic medium becomes minor in basic. You have to only find out the more stable alkene and the more stable carbon. It's a different thing. No. Do you understand?