If 2-methyl-2-pentene were converted into 1-hexene, what kind of reaction would that be?

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All right. Hi, everyone. So this question says that the reaction where three methyl hea 15 dyne is converted into Hep 15 dyne is what kind of reaction option? A says addition, option B says elimination, option C says substitution and option D says rearrangement. So the first thing I'd like to do is actually draw out our reactant in our product, right? Our starting material is three methyl hea 15 diane, which is a six carbon chain with one methyl substituent on carbon three, one double bond in between carbons, one and two and another in between carbons five and six. So now this compound gets converted into Hep the 15 die. So that's a seven carbon chain with a double bond in between carbons, one and two and another in between carbons five and six. So now that we have a better idea on what our starting material in our product look like. I want to go ahead and quickly talk about all of the reactions described in the answer choices because we can distinguish between addition, a liberation substitution and rearrangement, right? Recall that an addition reaction generally involve two reactant or starting materials combining together to form one larger product. So if we consider the, the reaction that's taking place over here, we wouldn't be able to necessarily say that the product is larger than the reactant, right? Because notice how our starting material has seven carbons and two double bonds, whereas our product also has seven carbons and two double ones. So option A would be incorrect in this case, because in this case, there are no two reactants that are combining to form a product that is that is larger. In fact, in terms of the size, the size of the reactant is the same as the size of the product approximately. Now, elimination is the opposite of reaction of addition. Excuse me, because elimination involves one larger reactant splitting into two or more smaller products. So those smaller products were once part of the larger structure and they have since been removed or eliminated, so to speak to form separate products. Now again, elimination would not necessarily apply in this case either because the product is not smaller than the reactant. In fact, their size is approximately the same. Now, substitution involves some kind of exchange between the two reactants to give two separate products, right? So functional groups or other parts of both molecules exchange with each other to form two new products. So substitution is not quite correct either because there are no two reagents in this case that are essentially exchanging parts of themselves. Now, last but not least we have a rearrangement which if you recall implies some kind of reorganization of the structure as a whole, right, the product of a rearrangement reaction is an isomer of the starting material because it's not that the number of atoms of the molecule or in the molecule is going to change, but rather the connections in between atoms are going to change, they're going to be reorganized to produce a different structure with the same number of atoms. And that is exactly what's happening here, right? Because the number of carbons is the same, it's seven for both sides and the number of double bonds is also the same. This is this indicates that all of the atoms in the reactant and the product have not changed, right? They still have those atoms in common. It's just that now they have a different structure. So option d in the multiple choice is correct because this is a rearrangement and there you have it. So with that being said, thank you so very much for watching and I hope you found this helpful.

If 2-methyl-2-pentene were converted into 1-hexene, what kind of reaction would that be?

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Key Concepts

Elimination Reaction

Hydrocarbon Structure

Rearrangement Reaction