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In a reaction (as given in my textbook),

$$\ce{R-CH=CH2 + (CH3-CO)2O -> R-CH2=CH-COCH3}$$

an alkene reacts with acetic anhydride to give methyl alkenyl ketone.

I am not sure of how this proceeds, a search on google displays no links to any relevant matter, and I have not successfully found this reaction in any of the other books I possess.

According to me, it should have been an addition reaction (characteristic of alkenes) across the double bond. But this isn't the case here. So, what exactly is the reaction mechanism?

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This is the Friedel-Crafts acylation reaction of alkene. Catalyzed by Lewis acid. Addition-elimination mechanism.

Mechanism

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  • $\begingroup$ "The Friedel–Crafts reactions are a set of reactions developed by Charles Friedel and James Crafts in 1877 to attach substituents to an aromatic ring" - Wikipedia (read the whole Friedel Craft Reactions page), I am not as yet aware of any non-aromatic Friedel-Craft, any pointers or links would be much appreciated, thanks a lot.... $\endgroup$ – Kaustubh May 24 '14 at 13:19
  • $\begingroup$ This was the only relevant article I found after a long search but that too gives just a 'page review' perhaps you could link something better thanks.. pubs.rsc.org/en/content/articlelanding/1972/cs/… $\endgroup$ – Kaustubh May 24 '14 at 13:21
  • $\begingroup$ Here is the reference. Only first page is free. But you can see the introduction about that. pubs.rsc.org/en/content/articlelanding/1972/cs/… $\endgroup$ – Ian Fang May 24 '14 at 15:16
  • $\begingroup$ Here is another link. It is full text. metzger.chemie.uni-oldenburg.de/download/83_engl.pdf $\endgroup$ – Ian Fang May 24 '14 at 15:17

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