2008

Enantioselective synthesesO 0031 Catalytic Asymmetric Generation of (Z)-Disubstituted Allylic Alcohols. — A

one-pot method for the synthesis of enantioenriched Z-disubstituted allylic alcohols, e.g. (IV) and (VIII), is introduced. Key feature is the inhibition of intermediary formed LiCl by product with tetraethylethylenediamine, since LiCl promotes the non-stereo-selective vinyl addition to aldehydes and thus gives racemic product. A wide range of chiral Z-disubstituted allylic alcohols is thus obtained in up to 98% e.e., including those derivatives hardly obtainable by other methods [cf. (X)]. The reaction tolerates various functional groups and is successfully coupled with the diastereoselective epoxidation of allylic alcohols [cf. (V)]. — (SALVI, L.; JEON, S.-J.; FISHER, E. L.; CARROLL, P. J.; WALSH*, P. J.; J. Am. Chem. Soc. 129 (2007) 51, 16119-16125; Dep. Chem., Univ. Pa., Philadelphia, PA 19104, USA; Eng.) — Mischke

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