SYNTHETIC APPLICATION 17 The para rearrangement is also a first-order reaction, and the rate is not greatly affected by acetic acid or dimethylaniline. 70 The non-occur-rence of inversion, and the atomic distances involved, make a cyclic mechanism improbable. The rearrangement may go through a first-order dissociation of the allyl ether into either radicals or ions, which must then be assumed to recombine, with ,the allyl group entering the para position, before any secondary reactions can take place. If -allyl radicals (or ions) actually were free during the reaction, they should com-bine with a reactive solvent such as dimethylaniline, and the yield of re-arrangement product would be low, which is contrary to the observed facts. A study 70 ° of the decomposition of quaternary ammonium com-+ pounds of the type [Me 2 N(C6H 5 )C 3 H5] [OAr]~ indicates that ions are not intermediates in the Claisen rearrangement. From the rearrange-ment of benzyl phenyl ether in quinoline at 250°, Hickinbottom
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This note was uploaded on 11/20/2011 for the course CHM 2210 taught by Professor Reynolds during the Fall '01 term at University of Florida.