Tertiary Amine Lewis Base Catalysis in Combination with Transition Metal Catalysis

Abstract

The cooperation between two orthogonal catalytic events during the formation of carbon-carbon and carbon-heteroatom bonds has emerged as an effective strategy for enantioselective chemical synthesis. In recent years, a number of pioneering investigations have described useful chemical synthesis methods whereby the reactivity or nucleophile-electrophile combinations can be fine-tuned or extended far beyond the effect and influence of a single catalyst. The recognition of this has had profound implications for the development cooperative catalysis as a field and has provided a foundation for the development of broadly useful chemical synthesis methods. This chapter focuses on the combination of tertiary amine Lewis base and transition metal catalysts, which the authors hope will simulate further developments and advances.

Synergistic Catalysis Involving Palladium for Stereodivergent Csp3–Csp3 Coupling Reactions

“…In 2013, Carreira and co-workers reported pioneering work involving dual iridium and amine catalysts for stereodivergent α-allylic alkylation of aldehydes (Figure A). − Since then, synergistic catalysis − has emerged as a powerful and commonly used strategy for achieving stereodivergent synthesis (Figure B). − The Zhang and Wang research groups have independently reported on an iridium/copper bimetallic system that enables stereodivergent allylation of aldimine esters. The Hartwig group has employed a synergistic iridium/copper catalysis method for stereodivergent allylation of azaaryl acetamides.…”

Recent progress in asymmetric synergistic catalysis – the judicious combination of selected chiral aminocatalysts with achiral metal catalysts

“…Recently, Snaddon has reviewed the general combination of chiral tertiary amine Lewis base catalysis with chiral transition metal catalysis. 14 This review will inspect developments since 2016 in the deployment of a chiral aminocatalyst with an achiral metal catalyst. Specifically, the reactions we will analyse here are examples of ‘Type I’ systems in which each catalyst acts independently and fully cooperatively.…”

Synergistic Ni/Pd Catalysis for Asymmetric Allylic Alkylation of 2-Acyl Imidazoles

“…Recently, to address these issues, a synergistic strategy has been adopted where a second chiral catalyst is used to activate the pronucleophiles and provide stereocontrol during the bond-forming events (Figure b). − In 2016, Snaddon and co-workers reported the use of a chiral Lewis base and an achiral Pd-complex in the direct α-allylation of perfluorophenyl arylacetic esters, wherein the stereocontrol was provided by the nucleophilic chiral Lewis base catalyst rather than the Pd-based ligand frameworks . In 2018, Shimizu, Kanai, and co-workers developed a boron/palladium dual catalysis for an asymmetric migratory α-allylation of allyl esters, resulting in α-allyl carboxylic acids containing an α-quaternary stereocenter .…”