Aldol reaction using tin enolates

The aldol reaction is one of the most useful and classical reactions in organic synthesis, since the resulting p-hydroxycarbonyl compounds are highly useful building blocks for pharmaceuticals and natural products.14 The asymmetric version of this reaction has been developed to a significant extent. We focus here on the asymmetric classical aldol reaction using a silver catalyst and related reactions.15 

In 1997, Yamamoto, Yanagisawa, and others reported the asymmetric reaction catalyzed by a BINAP-AgOTf catalyst (Table 9.7).16 The reaction was conducted with tributyltin enolate and aldehydes in the presence of the BINAP-AgOTf catalyst to afford the corresponding adduct with high enantioselectivity. The observed 

TABLE 9.8. Aldol Reaction Using Catalytic Amounts of Me3SnOMe 

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