Asymmetric conjugate addition of diethylzinc to cyclohexen‐2‐one, chalcone, and benzalacetone has been found to occur with 0.5% copper(II) triflate and 1% chiral phosphite. Cyclic phosphites derived from TADDOL gave excellent to moderate enantiomeric excesses. The nature of the exocyclic substituent of the dioxaphospholane ring is important, but the chiral induction is imposed by the TADDOL framework. Syntheses of all the TADDOL ligands are described.

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Asymmetric Conjugate Addition of Diethyl Zinc to Enones with Tartrate Chiral Phosphite Ligands. -The title reaction is investigated in order to gain a better understanding of the factors which affect the efficiency of chiral phosphite ligands in this reaction. -(ALEXAKIS, A.; VASTRA, J.; BURTON, J.; MANGENEY, P.; Tetrahedron: Asymmetry 8 (1997) 19, 3193-3196; Lab. Chim. Org.-Elem., CNRS, Univ. P. et M. Curie, F-75252 Paris, Fr.; EN)

Acceleration of the Conjugate Addition of Diethyl Zinc to Enones by Either Cu(OTf ) 2 or Trivalent Phosphorus Ligands.-In the presence of copper(II) triflate and triethylphosphite, conjugate addition of diethyl zinc to various enones is dramatically accelerated, yielding most of the corresponding adducts in 10-60 minutes. -(ALEXAKIS, A.; VASTRA, J.; MANGENEY, P.; Tetrahedron Lett. 38 (1997) 44, 7745-7748; Lab. Chim. Org.-Elem., CNRS, Univ. P. et M. Curie, F-75252 Paris, Fr.; EN)

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