Markovnikov's rule stated 'The hydrogen ends up attached to the carbon of the double bond that had more hydrogens to start with.' And many books give it a reason applying stability of carbocation. Carbocation stability is also important for Hammond postulate and rate of a reaction.

But the way I'd like to interpret it is using molecular orbital theory and hyperconjugation. If say C-H sigma bond in assymetric alkene(ie propene) hyperconjugated with pi* orbital, then the other carbon which have no hyperconjugation effect has more orbital coefficient (more pi orbital electron density). This means that the carbon without alkyl substituent is naturally more reactive to take proton. After that, we have tertiary carbocation, proceeding rest of reaction.

I used this concept a lot when I solve problems and found it very useful. However, I just figured that no books, no questions, no google infos suggested this idea at all. so, is this way of thinking wrong? if it's wrong, how so? if it's right, why nobody use it and why all curriculum stress Markovnikov's rule?

(I tried to find a image of asymmetric alkene MO but i couldn't. There is no image of it. But in a book, Oxford Organic Chemistry by Clayden, page 890 has similar image I was looking for. It's HOMO of 1,1-dimethylbutadien. 4th carbon has bigger orbital than the others as pi2 MO)


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