Why is tautomers not possible in benzoquinone? [closed]








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[![enter image description here](https://i.stack.imgur.com/b7tH7.png)](https://i.stack.imgur.com/b7tH7.png)1,4-Benzoquinone, commonly known as para-quinone, is a chemical compound with the formula $\ce{C6H4O2}$


When there are alpha Hydrogen's why can't it show tautomerism? 




You could sort of devise a tautomer by transferring an $\alpha$ hydrogen from carbon to oxygen. But if you draw the resulting structure you find a pair of cumulated double bonds. That tends to be unstable, and since the cumulated double-bonded carbons favor a 180° bond angle putting them into a relatively small ring makes them a lot more unstable. Your proposed tautomer is way out there in energy.


Tautomerization of a ketone works better when you have an $\alpha$ hydrogen **on a saturated carbon atom**.


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