# Most stable cation

I am facing difficulty in the following problem:

Which of the following cations is the most stable?

If we take the number of hyper conjugative structures into consideration then a) should be most stable. It is known that $\ce{-OH}$ is a $\ce{-I}$ group. So if it is present nearer to the carbonation it must destabilise it.Near the carbonation $\ce{-I}$ effect should be more effective than $\ce{+M}$ effect. However my textbook gives the answer as c). Is there something that I am missing out? Thanks.

• @aniline think about the lone pairs on the oxygen atom and how they can contribute Dec 25 '16 at 22:38
• @getafix Yes it's true that $OH$ group will also exert $+M$ effect.But since it is very close to the carbonation its inductive effect should dominate over the mesomeric effect.Moreover mesomeric effect should be neglected since it will bring about a positive charge on more electronegative oxygen.
– Pink
Dec 26 '16 at 1:28
• What does a carbocation look like? How is the p orbital positioned. How are the lone pairs on oxygen atom positioned? Can electrons transfer from oxygen to the vacant p orbital ? How does the inductive effect work? Think about these questions. I'm afraid I cannot write up a complete explanation right now Dec 26 '16 at 1:48
• (c) is not a carbocation per se. There is a better resonance structure.
– Zhe
Dec 26 '16 at 23:39
• Please at least promote or improve this question instead of down voting or voting to close so that the requisite correct explanation could be brought forward.My attempts are quite clear in the question and comments above.
– Pink
Dec 28 '16 at 2:28