A Readily Accessible Class of Chiral Cp Ligands and their Application in RuII -Catalyzed Enantioselective Syntheses of Dihydrobenzoindoles

Shou-Guo Wang; Sung Hwan Park; Nicolai Cramer

doi:10.1002/anie.201802244

A Readily Accessible Class of Chiral Cp Ligands and their Application in Ru^II -Catalyzed Enantioselective Syntheses of Dihydrobenzoindoles

Angew Chem Int Ed Engl. 2018 May 4;57(19):5459-5462. doi: 10.1002/anie.201802244. Epub 2018 Apr 6.

Authors

Shou-Guo Wang¹, Sung Hwan Park¹, Nicolai Cramer¹

Affiliation

¹ Laboratory of Asymmetric Catalysis and Synthesis, EPFL SB ISIC LCSA, BCH 4305, 1015, Lausanne, Switzerland.

PMID: 29528173
DOI: 10.1002/anie.201802244

Abstract

Chiral cyclopentadienyl (Cp^x ) ligands have a large application potential in enantioselective transition-metal catalysis. However, the development of concise and practical routes to such ligands remains in its infancy. We present a convenient and efficient two-step synthesis of a novel class of chiral Cp^x ligands with tunable steric properties that can be readily used for complexation, giving Cp^x Rh^I , Cp^x Ir^I , and Cp^x Ru^II complexes. The potential of this ligand class is demonstrated with the latter in the enantioselective cyclization of azabenzonorbornadienes with alkynes, affording dihydrobenzoindoles in up to 98:2 e.r., significantly outperforming existing binaphthyl-derived Cp^x ligands.

Keywords: asymmetric catalysis; cyclization; cyclopentadienyl ligands; ligand design; ruthenium.

Publication types

Research Support, Non-U.S. Gov't