Kinetic Resolution of Epoxides by a CC Bond-Forming Reaction: Highly Enantioselective Addition of Indoles to cis, trans, and meso Aromatic Epoxides Catalyzed by [Cr(salen)] Complexes†
Marco Bandini Dr.
Dipartimento di Chimica “G. Ciamician”, Università di Bologna, Via Selmi, 2 40126 Bologna, Italy, Fax: (+390) 51-2099456
Search for more papers by this authorPier Giorgio Cozzi Prof. Dr.
Dipartimento di Chimica “G. Ciamician”, Università di Bologna, Via Selmi, 2 40126 Bologna, Italy, Fax: (+390) 51-2099456
Search for more papers by this authorPaolo Melchiorre Dr.
Dipartimento di Chimica “G. Ciamician”, Università di Bologna, Via Selmi, 2 40126 Bologna, Italy, Fax: (+390) 51-2099456
Search for more papers by this authorAchille Umani-Ronchi Prof. Dr.
Dipartimento di Chimica “G. Ciamician”, Università di Bologna, Via Selmi, 2 40126 Bologna, Italy, Fax: (+390) 51-2099456
Search for more papers by this authorMarco Bandini Dr.
Dipartimento di Chimica “G. Ciamician”, Università di Bologna, Via Selmi, 2 40126 Bologna, Italy, Fax: (+390) 51-2099456
Search for more papers by this authorPier Giorgio Cozzi Prof. Dr.
Dipartimento di Chimica “G. Ciamician”, Università di Bologna, Via Selmi, 2 40126 Bologna, Italy, Fax: (+390) 51-2099456
Search for more papers by this authorPaolo Melchiorre Dr.
Dipartimento di Chimica “G. Ciamician”, Università di Bologna, Via Selmi, 2 40126 Bologna, Italy, Fax: (+390) 51-2099456
Search for more papers by this authorAchille Umani-Ronchi Prof. Dr.
Dipartimento di Chimica “G. Ciamician”, Università di Bologna, Via Selmi, 2 40126 Bologna, Italy, Fax: (+390) 51-2099456
Search for more papers by this authorWe thank MIUR, Rome (FIRB funds), “Progetto Stereoselezione in Chimica Organica – Metodologie ed Applicazioni”, and the University of Bologna (funds for selected research topics) for financial support of this research.
Graphical Abstract
The high reactivity of indoles has led to a new approach for the kinetic resolution of epoxides. [Cr(salen)] efficiently catalyzes a new CC bond-forming reaction that allows the kinetic resolution of cis and trans aromatic epoxides (see scheme). By employing the same catalytic system, different indolyl derivatives were obtained in high enantiomeric excesses (up to 98 %) by asymmetric ring opening of meso-stilbene oxide.
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