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andselisk ♦
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hyperconjugation Hyperconjugation in cresol

In cresol both +I$+I$ effect as well as hyperconjugation work together to determine its acidity. whenWhen the methyl group is present in the orthoortho- and para positionpara-position both of them can act upon phenol. Hyperconjugation

Hyperconjugation as a rule dominates which increases the electron density of the aryl. ThisThis makes it less acidic because the conjugate base is now less stable. ButBut when its meta cresol hyperconjugationmeta-cresol, hyperconjugation no longer works. 

Why is it so? itIt happens even though an empty p orbital$\mathrm{p}$-orbital is present near the alpha hydrogen$\alpha$-hydrogen. What moreWhat else does it need?

hyperconjugation in cresol

In cresol both +I effect as well as hyperconjugation work together to determine its acidity. when the methyl group is present in the ortho and para position both of them can act upon phenol. Hyperconjugation as a rule dominates which increases the electron density of the aryl. This makes it less acidic because the conjugate base is now less stable. But when its meta cresol hyperconjugation no longer works. Why is it so? it happens even though an empty p orbital is present near the alpha hydrogen. What more does it need?

Hyperconjugation in cresol

In cresol both $+I$ effect as well as hyperconjugation work together to determine its acidity. When the methyl group is present in the ortho- and para-position both of them can act upon phenol.

Hyperconjugation as a rule dominates which increases the electron density of the aryl. This makes it less acidic because the conjugate base is now less stable. But when its meta-cresol, hyperconjugation no longer works. 

Why is it so? It happens even though an empty $\mathrm{p}$-orbital is present near the $\alpha$-hydrogen. What else does it need?

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Esha Mukhopadhyay
Esha Mukhopadhyay
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hyperconjugation in cresol

In cresol both +I effect as well as hyperconjugation work together to determine its acidity. when the methyl group is present in the ortho and para position both of them can act upon phenol. Hyperconjugation as a rule dominates which increases the electron density of the aryl. This makes it less acidic because the conjugate base is now less stable. But when its meta cresol hyperconjugation no longer works. Why is it so? it happens even though an empty p orbital is present near the alpha hydrogen. What more does it need?