Reactions of Allyl and Vinyl Anions

Reactions of Allyl and Vinyl Anions. A brief summary of some key reactions reported in this area is recorded here. This area is also partly covered in Chapter 8. The results are summarized in Table 11. A comparison of the reactivity of ene-sulphides and ene-ethers towards organometallic reagents revealed remarkable differences. With thio compounds metallation at the olefinic site next to the heteroatom dominates clearly over the alternative deprotonation of an allylic position. Only with propenyl phenyl sulphide were both exchange modes observed simultaneously, whereas in all higher homologues as well as vinyl phenyl sulphide the metal was exclusively attached to the olefinic a-carbon atom.  

Stereospecific route to terminal alkenyl-lithium reagents 

Alexakis, A. Commer on, J. Villieras, and J. F. Normant, Tetrahedron Letters, 1976, 2313. 

Efficient trapping of the vinyl carbanion intermediate. Aldehyde tosylhydrazones cannot be used 

Pivaloyl nitrene, generated photolytically from pivaloyl azide, adds to olefins stereospecifically in its singlet state and stereoselectivily in its triplet state. Dichloro- 

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