Carbocation is a positively charged carbon ion(C+). It is an intermediate generally formed during organic reactions. They exhibit a special quality called 'rearrangement' by virtue of which less stable carbocations can rearrange to form more stable carbocations during the reaction. The actively ...

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Mechanism for acid-catalyzed dehydration of 2,3-dimethylcyclopentanol

How do you get from 2,3-dimethylcyclopentanol to 1,2-dimethylcyclopent-1-ene? I know the -OH group leaves as water (being protonated by acid) forming a carbocation. Then the weak nucleophile (water) ...
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Which carbocation is more stable , the one attached to methyl or the one attached to ethyl?

$\ce{C2H5+ vs \ C3H7+}$ There are two conflicting trends here. Inductive effect of ethyl will be higher than that of methyl so carbocation attached to ethyl ( 3 carbons in total) should be more ...
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Can Hydride Shift and Methyl shift happen one after another in a carbocation?

Can hydride shift be followed by methyl shift for stabilizing a carbocation? In case both is possible which will occur first?
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Carbocation stability order

I was wondering whether the following order is correct : In the first inequality, how come 9 hyperconjugation dominated resonance effect of benzene ring? In the last inequality doesn't 2 ...
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How does a carbocation have a positive charge?

When an alkene bonds with an H+ ion, the electron pair from the pi bond goes towards a new dative covalent bond with the hydrogen ion, leaving, on one side of the old double bond, a carbon bonded to ...
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Carbocation rearrangement in alkene addition reaction

This is a question from my textbook: Determine a step-wise $S_N1$ mechanism for the overall reaction: The solution shows the following carbocation rearrangement after Bromine leaves in the ...
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Why cyclopropylmethyl carbocation is more stable Benzyl carbocation?

I know in tri cyclopropylmethyl carbocation the hybridization of carbocation will be pushed to $sp^2$ but how? Can someone explain this to me by drawing resonance structures for tri cyclopropyl methyl ...
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Instability of vinylic and arylic carbocations

I have checked the net a lot and read quite a few books, but I still am not able to understand why vinylic and arylic carbocations are so unstable. Can someone please help For arylic carbocation, the ...
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Stability of cyclobutyl methyl carbocation

I know that cyclopropyl methyl carbocation is exceptionally stable compared to say, benzyl carbocation. But I want to know how stable is cyclobutyl methyl carbocation compared to say, ...
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Why does carbocation stability increase in the order 1°, 2°, 3°?

I'm reading about $\:\mathrm{S_N1}$ and $\:\mathrm{S_N2}$ reaction mechanisms. 1° carbocations are unstable to the point of not having been observed in solution, ever. 2° are more stable, and 3° ...
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Resonance in carbocation derived from allenes

During a reaction if addition on one of the $\pi$ bonds of an allene(containing even number of $\pi$ bonds like $\ce {H2C=C=CH2}$) takes place then a carbocation is formed. To decide the position of ...
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Preparation of alkyl halide from alcohols

$\ce{R-OH + HBr -> R-Br + H2O}$ An $\ce{R+}$ carbocation is formed during this reaction. If $\ce{R}$ is any alkyl group instead of methyl or ethyl, can the beta hydrogen to the hydroxy group be ...
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Why are isomers difficult to separate?

I recently learned that attempts to compare the spectra of two isomers of $\ce{C_3H_3^+}$ were frustrated by the difficulty of separating the two species. What makes these isomers difficult to ...
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Precedence of 1,2 carbocation rearrangement

How can one choose which group has more shifting tendency in 1,2 carbocation rearrangement? The obvious order is via the stability of the carbocation of the group. But, phenylic groups have high ...