Why is the Major Organic product of (z)-3-methylhex-3-ene + HBr, 3-bromo-3-methy

Question

Why is the Major Organic product of (z)-3-methylhex-3-ene + HBr,  3-bromo-3-methylhexane? During the reaction, the H from the HBr bonds to the alkene and brakes the pi bond, so there is a carbocation and then the Br bonds to help out the carbocation. I dont understand how you know which carbon is going to bond to the H and which one will become the carbocation and eventually bond to the Br?

Why is the Major Organic product of (z)-3-methylhex-3-ene + HBr, 3-bromo-3-methylhexane? During the reaction, the H from the HBr bonds to the alkene and brakes the pi bond, so there is a carbocation and then the Br bonds to help out the carbocation. which carbon is going to bond to the H and which one will become the carbocation and eventually bond to the Br?

Explanation / Answer

In order to understand the formation of carbocation (carbon with +ve charge) you need to understand that the products or intermediates which are more stable are formed.

Now, Me (-CH3) group in organic chemistry act as small electron donating group.

Also, greater the charge density, greater is the energy and less stable is the product.

Now, in the two carbocation formed, The one which is formed in the above case has 3 methyl group (or can be any other alkyl group) while the other possibility would have just 2, making the above one more stable, due to lesser charge density.

This whole effet is explain by the rule "Markovinkov addition".

This states that while addition of HX, X adds to the carbon with greater number of alkyl group attached to it.

Hope this helps. Comment for doubts..

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