Role of 2-oxonia Cope rearrangements in Prins cyclization reactions
S D Rychnovsky1, S Marumoto, J J Jaber
1Department of Chemistry, 516 Rowland Hall, University of California, Irvine, California 92697-2025, USA. srychnov@uci.edu
Abstract:
[reaction--see text] The 2-oxonia Cope rearrangement is undetectable in typical Prins cyclization reactions. We have investigated the Cope rearrangement in a Prins cyclization reaction using a competitive reduction of the oxocarbenium ion intermediate, and a racemization reaction mediated by the rearrangement. In our unactivated substrate, the 2-oxonia Cope rearrangement was much faster than Prins cyclization. An enantioselective allyl transfer reaction also was developed using a 2-oxonia Cope rearrangement.
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