Novel access to chiral 1,1′-disubstituted ferrocene derivatives via double stereoselective cyanohydrin synthesis exploiting the hydroxynitrile lyase from Hevea brasiliensis

A novel route to chiral ferrocene derivatives involving the application of hydroxynitrile lyase from Hevea brasiliensis has been developed. The method allows the conversion of formylferrocene 1 and 1,1′-diformylferrocene 2 into their corresponding chiral cyanohydrins. (R)-(Cyanohydroxymethyl)ferrocene 3 and (R,R)-1,1′-bis(cyanohydroxymethyl)ferrocene 4 were obtained in high yield and stereochemical purity using this method. The full structural characterisation of the latter including the determination of diastereomeric purity and the assignment of the absolute configuration is disclosed. [Copyright &y& Elsevier]