Cross-coupling involving carbonyl compounds

Mainly for practical reasons, other topics are discussed in other parts. In addition to Pd-catalyzed cross-coupling involving allyl, propargyl, and allenyl derivatives discussed in Sects, ni.2.9 and m.2.10, allylpalladation and related reactions with alkenes, alkynes, and other 7r-compounds, which can best be viewed as carabopalladation processes, are discussed in Sect. IV.4, while carbonylation and related reactions of allylpalladium and related derivatives are discussed in Sect. VI.3. 

The use of enol- and phenol-esters in cross-coupling reactions is a valuable protocol, as it gives an indirect way to involve readily available phenols and carbonyl compounds as the electrophilic components of cross-couplings (Equation (22)) ... 

Cross-coupling of silyl enol ethers and allylic silanes. The formation of y,S-unsaturated carbonyl compounds involves one-electron oxidation. 

Application of Pd-catalyzed cross-coupling to a-aIkynylation,F30 a-alkenylation, and a-arylationF3 of heteroaromatic a,/3-unsaturated carbonyl derivatives, such as 5-iodouracil derivatives, has been known since the early 1980s (Scheme 50). Although these reactions are formally related to the Pd-catalyzed a-substitution discussed herein, the robust aromatic nature of the heteroaromatic substrates makes the requirements for their a-substitution less demanding. These reactions should therefore be viewed as a class of cross-coupling reactions involving aryl halides rather than a-halo-a,jS-unsaturated carbonyl compounds. In most... 

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