Allyl carbonates solid support

Another possibility is to dissolve the catalyst in water, which is supported on a solid phase such as silica. The catalyst is not directly anchored to the solid phase but is dissolved in a film of water, which in turn is linked to the surface of the solid. This approach is termed supported aqueous phase catalysis (SAPC) and has successfully been applied to allylic carbonates. " " ... 

B.vi.b. Coupling of Building Block to Solid Support Via jr-Allylpalladium Complexes. The reactions of immobilized nucleophiles with 7r-allylpalladium precursors have been described for various combinations.f A double allylation reaction has been shown using an immobilized nitrogen nucleophile with 2-hydroxymethylallyl methyl carbonate. After the first allylic substitution, acylation and a subsequent coupling with various nucleophiles provided access to substituted glycine derivatives (Scheme 22). ... 

Allylation of carbonyl compounds is another very useful carbon-carbon bond forming asymmetric transformation in organic synthesis. This transformation yields the homoallylic alcohols that have proven to be valuable reagents and intermediates that have found numerous applications in natural product total synthesis. In particular, asymmetric allyl-boration of aldehydes employing tartrate- and pinane-derived reagents has been widely exploited. Although the asymmetric allylation reaction is well documented and widely used in solution phase, the asymmetric variant of the allylation of carbonyl compounds on the solid support has remained largely unexplored. ... 

A-Protected amines were assembled on solid-phase via sulfonamide-based handle 58 (Scheme 27) [67]. Tertiary sulfonamides were generated upon reaction with allylic, benzylic and primary alcohols under Mitsu-nobu conditions. Secondary amines were released from the support using mild nucleophilic conditions such as treatment with thiophenol and potassium carbonate. 

C-Alkylations have been performed with both support-bound carbon nucleophiles and support-bound carbon electrophiles. Benzyl, allyl, and aryl halides or triflates have generally been used as the carbon electrophiles. Suitable carbon nucleophiles are boranes, organozinc and organomagnesium compounds. C-Alkylations have also been accomplished by the addition of radicals to alkenes. Polystyrene can also be alkylated under harsh conditions, e.g. by Friedel-Crafts alkylation [11-16] in the presence of strong acids. This type of reaction is incompatible with most linkers and is generally only suitable for the preparation of functionalized supports. Few examples have been reported of the preparation of alkanes by C-C bond formation on solid phase, and general methodologies for such preparations are still scarce. 

One important method for the oxidation reaction using Pd(II) is a gas phase reaction using a solid Pd catalyst supported on active carbon or alumina. Actually vinyl acetate and allyl acetate are produced commercially in a gas phase by using the supported Pd catalyst. It is assumed that Pd(0) is oxidized efficiently to Pd(II) with oxygen on the surface of the support. 

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