Aliphatic and Aromatic Claisen Rearrangement

I 3 Aliphatic and Aromatic Claisen Rearrangement 3.2.4.3 Brensted Acid Catalyst... 

The comparison of experimental and theoretically predicted kinetic isotope effects (KIEs) can be used to probe the accuracy of the computationally predicted transition structure provided that the experimental KIEs have been determined accurately. A comparison of predicted and experimental KIEs by Meyer et al. [55] led to the conclusion that, There is a firm disagreement in about half the cases between predicted and literature experimental heavy atom KIEs for both the aliphatic and aromatic Claisen rearrangements . Therefore, they reinvestigated the experimental KIEs for the Claisen rearrangement of aUyl phenyl and allyl vinyl ether and compared the determined values (solution) with the calculated data (gas phase). Eor the Claisen rearrangement of allyl vinyl ether, the transition structure was calculated on the MP4(SDQ)/6-31G level of theory and the predicted KIEs were in excellent agreement with the new experimental KIEs. The authors collected and compared previously reported data for the calculated distance between C- l/C-6 and O/C-4 and added their own predicted data (Scheme 11.40). 

The thermal rearrangement of allyl phenyl ethers to o-allyl phenol and its mechanism is very well known to organic chemists. Both the aliphatic and aromatic Claisen rearrangements involve a 3,3-sigmatropic shift. There are reviews providing usefulness of this rearrangement reaction. ... 

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