Homoallylic amides, formation

Ham et al. [60] used an unselective attack of a vinyl Grignard reagent on the iST-benzoyl-protected phenylalaninal 92 to generate alcohols 93 (Scheme 25). A tmns-selective, Pd(0)-catalyzed oxazoline formation starting from the homoallylic amide 93 was subsequently employed to build up the (S)-configuration at carbon atom C-3 of oxazoline 94. 

Some examples of photolytic intramolecular [2 + 2] cycloadditions which lead to the formation of lactones and lactams are sketched in Scheme 9.9. The allyl ester and N-monosubstituted amide do not undergo cydization, probably because of the high energy of the required E conformers. Cydization of the homoallyl ester does,... 

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