Enantioselective Conjugate Addition of Dialkylzinc Reagents to Cyclic and Acyclic Enones Catalyzed by Chiral Copper Complexes of New Phosphorus Amidites†
André H. M. de Vries
Department of Organic and Molecular Inorganic Chemistry University of Groningen Nijenborgh 4, NL-9747 AG Groningen (The Netherlands) Fax: Int. code +(50) 363-4296 e-mail: [email protected]
Search for more papers by this authorAuke Meetsma
Department of Organic and Molecular Inorganic Chemistry University of Groningen Nijenborgh 4, NL-9747 AG Groningen (The Netherlands) Fax: Int. code +(50) 363-4296 e-mail: [email protected]
Search for more papers by this authorCorresponding Author
Prof. Dr. Ben L. Feringa
Department of Organic and Molecular Inorganic Chemistry University of Groningen Nijenborgh 4, NL-9747 AG Groningen (The Netherlands) Fax: Int. code +(50) 363-4296 e-mail: [email protected]
Department of Organic and Molecular Inorganic Chemistry University of Groningen Nijenborgh 4, NL-9747 AG Groningen (The Netherlands) Fax: Int. code +(50) 363-4296 e-mail: [email protected]Search for more papers by this authorAndré H. M. de Vries
Department of Organic and Molecular Inorganic Chemistry University of Groningen Nijenborgh 4, NL-9747 AG Groningen (The Netherlands) Fax: Int. code +(50) 363-4296 e-mail: [email protected]
Search for more papers by this authorAuke Meetsma
Department of Organic and Molecular Inorganic Chemistry University of Groningen Nijenborgh 4, NL-9747 AG Groningen (The Netherlands) Fax: Int. code +(50) 363-4296 e-mail: [email protected]
Search for more papers by this authorCorresponding Author
Prof. Dr. Ben L. Feringa
Department of Organic and Molecular Inorganic Chemistry University of Groningen Nijenborgh 4, NL-9747 AG Groningen (The Netherlands) Fax: Int. code +(50) 363-4296 e-mail: [email protected]
Department of Organic and Molecular Inorganic Chemistry University of Groningen Nijenborgh 4, NL-9747 AG Groningen (The Netherlands) Fax: Int. code +(50) 363-4296 e-mail: [email protected]Search for more papers by this authorWe thank Prof. Dr. P. Knochel, University of Marburg, for the opportunity given to A. H. M. de Vries to perform some experimental work in his laboratories, and Dr. R. Hulst, University of Groningen, for initial syntheses.
Graphical Abstract
Monodentate phosphorus amidites like 1 and Cu(OTf)2 provide access to the first chiral complexes that catalyze the enantioselective conjugate addition of organozinc reagents to cyclic as well as acyclic enones. The ligand-accelerated process affords β-substituted ketones in excellent yields and with high ee values. Functional groups in the zinc reagent are tolerated.
References
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