Alkylation of Active Methylene Compounds with Alcohols

Alkylation of Active Methylene Compounds with Alcohols 

The carbon- arbon bond-forming reactions based on hydrogen transfer catalyzed by Cp Ir complex have been extended to the alkylation of active methylene compounds. Grigg et al. reported the alkylation of arylacetonitriles catalyzed by the 

Entry Secondary alcohol Primary alcohol Catalyst (mol% Ir) Base Yield (%)  

Hydrogen transfer oxidation of an alcohol to give an aldehyde and an iridium hydride. 

Base-promoted Knoevenagel condensation to give an alkylated arylacrylonitrile. 

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The dianions of /S-keto-esters undergo Claisen ester condensation in the expected manner via the y-carbanion. In an extension of a method reported for the preparation of amines from alcohols loc. cit.), the same Japanese authors have described the direct alkylation of active methylene compounds with alcohols (Scheme 42) the method is limited to relatively acidic compounds, with pJ Tg < 11 diethyl malonate (pX 13.3) does not react. 

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