Linalool $\left(\mathrm{C}_{10} \mathrm{H}_{18} \mathrm{O}\right)$ is found in lavender flowers and is one of the constituents of lavender oil. It has a single chiral centre and both $R$ and $S$ enantiomers (see Section 18.4, p.845) are found in lavender oil. To determine the structure of linalool, the following reactions were carried out. (Sections $21.3$ and 21.4)
(a) Use the information in reaction 1 to determine the number of $\mathrm{C}=\mathrm{C}$ bonds in linalool.
(b) From the products in reaction 2, what are the two possible structures of linalool?
(c) Use the information in reaction 3 to determine the structure of linalool.
(Hint. Disiamyiborane reacts with a C=C bond in a hydroboration reaction.)
(d) Explain why the reaction of disiamylborane with linalool is chemoselective. (Hint. Consider the size of disiamylborane.)

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Chapter 21

Alkenes and alkynes: electrophilic addition and pericyclic reactions

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Hello everyone. Let us see the following question. So we have lena lul which has a general formula of C 10 H 18. So we are talking about lena luthor to the general formula certain H 18 and oh that must be an alcohol, which is found in the lavender flowers. And it is one of the constituent of lomond of oil. It has a single cable center and both RNS and consumers are found in the lavender oil. To determine the structure of the following reactions were carried out. So let us see the reactions given in the question. So there is only the general formula of Lionel is given here. So we have to use the information and we have to find out the structure of 9 11. Now this lena luthor on hydrogenation over here in the reaction one, it gives the compound with the general formula C 10 H 12. And so we need to answer the question a related to this reaction one. So the question one or question a is use the information in reaction one to determine the number of CC double bonds he wants. So it is said that Lena Lowell. Lena loule has a general formula of certain H 18, Sorry H 18. And oxygen on hydrogenation partially with the help of poisoned palladium gives the general gives the product with the general formula C 10 H 22 oxygen. So we can see the number of carbon here is same. However, the number of hydrogen has changed from C 18 to see, sorry, age 18 to age 22. So we have added four hydrogen extra for hydrogen. So in each double bond we had two hydrogen to get a single bond. So that means there should be presence of C double bond. See there are two times so to carbon, carbon double bond should be there. So hence the answer is to see double bond C. So let us see the question be from here. So the question bees from the products in the reaction to what are the two possible products? Offal in olive oil. So we have seen the reaction to this ozone analysis. It has given us 03 that is oxidative ozone analysis in the presence of H 202. So normally knows analysis what we do suppose if there is a carbon double bond carbon here. So during ozone analysis we put the bridge to the double board. For our convenience, we add oxygen on both sides. So it becomes C double bond O and C double bond. Hence it is mentioned as oxidative stress analysis. We further oxidized the carbon to carbon oxalic acid in case if it is terminal carbon. Now. Using the information given here, let us use let us find out what are the possible structures that we can form. So according to the products given here in this question, you see it is the question where there is car box silly group. Sorry for my convenience, I would like to see double board. Whoa ohh group. Okay, and then the same carbon is connected to the carbon here which is connected to here with the H group and one metal go. This is further connected like this. See double born. Whoa. For my convenience I will put double born war facing this side. So now there is also one keto group given as a tone group and also one formic acid given. So what do you mean by Formica said it would have been generated like this, isn't it? It would have been generated like this and other side ketone group. That is C double bordeaux and here ch three and ch three. So this is that so that means we have to remove the oxygen and we have to put a double bond here. Okay for always before oxidation this ohh group would have been eliminated. Okay so let us write the structure of Lionel. All from here it is the carbon which has two metal groups. Okay, and then there is a double bond here. This carbon. Okay, this particular carbon is connected to the carbon which has metal group and a O. H. Group. Then this is here here here then there is a carbon here further has a double bond. So this is the stra possible structure of linen. Now this is one of the is a Marseille. If it is a day, the remaining structure of Lionel should be let me write a double bond. This flip it in the mirror image, I can write. Okay There are possible 12 See 1234567. So 12 three 45 six and seven. So totally thereon one two 345678. I will put so 1234 567367. And I will let me put the 81. So this is again branch here. So the carbon at position five has a metal group. And oh yeah it's a group. Okay, so these are the two possible structures of Lionel all with the D. N. E. L. Form. So now let's see the question. See the question see is use the information in reaction three to determine the structure of Lionel all so exact structure of Lionel. All we have to find out from the information given here it is broken like this, isn't it? So the possible structure of leaner lol should be this one. This is the possible structure of living alone. So I am just highlighting the structure. So this answer is same as C. So now this is anyway given as an answer for C. So now let us find out the answer for D. So in answer D explain why the reaction of died di CML boring with the is chemically selective. So it is already given their the structure of D. C. M. L. Boren. It is very bulky structure. Okay, which supplies which is used as a reducing agent which supplies the hydrogen C. We know that already in general there is a car box. There's all keen. We know that it is going to oxidize and whether it is oxidizing it is supposed to give a car Boxley group. As I explained in sub question. However, it is a reductive. Also an analysis means followed by hydro operation tie. Okay, So why it is can be selective because of the bulky nature of di CML boring. It is due to due to the bulky nature off day. See ya mild boring hydrogen from same side hence leads to stick. Therefore it is gimme selective Kimio selected. The reaction is chosen based on the chemical chosen based on the reducing agent chosen we get the related products. So chemical is important here to choose the product intensities. Chemical selective. Thank you.

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