Copper-Catalyzed Highly Enantioselective Synthesis of Cyclic Allylic and Homoallylic Alcohols with Dialkylzinc Reagents

Abstract

The copper-phosphoramidite catalyzed addition of dialkylzinc reagents to racemic or meso allylic epoxides can be synthetically exploited in different ways, depending on the substrates and reaction conditions used.

Key words

asymmetric catalysis - organozinc reagents - copper - kinetic resolution - desymmetrization

References

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• ( S,R,R )-Diastereoisomeric phosphoramidite, derived from (S)-BINOL and (R)-bis-phenylethylamine developed by Feringa et al. is to date one of the most effective chiral ligand for several copper-catalyzed enantioselective conjugate additions. For some recent examples, see:
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12

In this case, the use of lower amounts of the chiral catalyst (<1.0 mol%) gave a very sluggish reaction.