Phosphine Oxide and Phosphonate-Stabilized Anions

It is found that the sulfur-based groups are problematic in preparation and rearrangement of the functionahzed allyl vinyl ethers. It became apparent that the phosphorus-based groups as alternative anion-stabUizing moieties, mainly because of the ease of preparation of aUenylphosphoms precursors and a well-established chemistry of phosphorus-stabilized allyl anions [77]. 

At similar levels of substitution, the phosphonate rearranged 10-20 times faster than the corresponding suUbne (Eq. 3.1.62). The rearrangements of Cl monosub- 

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