Alkylation of enones

This section contains alkylations of ketones and protected ketones, ketone transpositions and annulations, ring expansions and ring openings and dimerizations. Conjugate reductions and Michael alkylations of enone are listed in Section 74 (Alkyls from Alkenes). 

Conjugate reductions and reductive alkylations of enones are listed in Section 74 (Alkyls from Alkenes). 

The ideal disconnection strategically is (19a) which separates the ring from the chain. This corresponds to the a-alkylation of enone (22) (as discussed on p 434) with alkyl halide (21),... 

One published synthesis follows strategy (b) but adds the ethyl group later by alkylation of enone (32) in the manner of TM (19). 

Mosca, R., Fagnoni, M., Mella, M., and Albini, A. (2001) Synthesis of monoprotected 1,4-diketones by photo-induced alkylations of enones with 2-substituted-1,3 -dioxolane s. Tetrahedron, 57, 10319-10328. 

Reductive alkylation of enones. Tin(IV) enolates are formed via the ketyls, which are derived from enones and BujSnH. Reaction of the enolates with aldehydes furnishes aldols. Quenching the enolates with alkyl halides in the presence of HMPA gives a-alkylated products. ... 

P-Alkylation of enones The adducts with enones undergo alkylation and then elimination of benzotriazole. 

Subsequently, they were the first to demonstrate that saturated alkyl halides 279 as sp hybridized electrophiles never before used in an organo-mediated MBH reaction facilitated the intramolecular a-alkylation of enones to afford five- and six-membered enone products 280 (Scheme 1.101). ... 

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