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Benzaldehyde + Ac2O

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Darkstar:
Benzaldehyde + acetyl anhydride in the presence of NaOAc. What kind of reaction is this? Just a common carbonyl alpha-substitution or something else? What do we get?

movies:
It's not an alpha substitution, there are no alpha protons in benzaldehyde.  I think that those are acylation conditions.  Sort of like Friedel-Crafts, but without a metal Lewis acid.  I think that you would get 3-formyl acetophenone.

falcon:
 :o
It`s classic Perkin condensation! Synthesis  of cinnamic (3-phenyl-2-propenoic) acids. Acetate anion
tears off the proton from acetic anhydride, this anion attack carbonyl group in benzaldehyde, further follows migration negative charge, leading to cinnamic acid.

Darkstar:
That's right... thanks, I see now.

movies:
Really?  But the acetate anion isn't nearly a strong enough base to remove that proton!

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