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For most ketones, hydrate formation is unfavorable, because the equilibrium favors the ketone rather than the hydrate. However, the equilibrium for hydration of hexafluoroacetone favors formation of the hydrate. Provide a plausible explanation for this observation.

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Final answer:

Hydration of hexafluoroacetone is favoured due to the strong electronegativity of the surrounding fluorine atoms, which stabilize the hydrate form by inductive effects, thus shifting the equilibrium toward the hydrate which is more stable in this case compared to most other ketones.

Step-by-step explanation:

The hydration of hexafluoroacetone is an interesting case in the realm of organic chemistry, primarily due to the presence of strongly electronegative fluorine atoms. In most ketones, hydrate formation is unfavorable with the equilibrium heavily favoring the ketone itself. This is because the formation of a hydrated ketone requires the creation of a less stable, more energetic structure compared to the original carbonyl group. However, in the case of hexafluoroacetone, the surrounding fluorine atoms withdraw electron density from the carbonyl carbon, increasing its positive character and making it more susceptible to nucleophilic attack by water molecules.

This increased electrophilic character of the carbonyl carbon in hexafluoroacetone makes the formation of the hydrate more thermodynamically stable than in other ketones. The fluorine atoms not only increase the carbonyl carbon's electrophilicity but also stabilize the negatively charged oxygen in the hydrate through inductive effects. Consequently, the equilibrium for the hydration of hexafluoroacetone shifts toward the hydrate, a rarity among ketones.

User Sean Shi
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Answer:

Hydrated form of hexafluoroacetone is highly stable.

Step-by-step explanation:

Hydrated form of hexafluoroacetone is highly stable due to presence of two five membered ring structures formed through hydrogen bonding between F and H (in -OH group).

Due to this stable structure,
H_(2)O can not escape the hydrated form and goes back to keto form.

The structure of hydrated form of hexafluoroacetone has been shown below.

For most ketones, hydrate formation is unfavorable, because the equilibrium favors-example-1
User Aditya Mishra
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