Metal-catalyzed enantioselective allylation, which involves the substitution of allylic metal intermediates with a diverse range of different nucleophiles or S(N)2'-type allylic substitution, leads to the formation of C-H, -C, -O, -N, -S, and other bonds with very high levels of asymmetric induction. The reaction may tolerate a broad range of functional groups and has been applied successfully to the synthesis of many natural products and new chiral compounds.

Metal-catalyzed enantioselective allylation in asymmetric synthesis.

Asymmetric catalysis with transition-metal complexes is the basis for a vast array of stereoselective transformations and has changed the face of modern synthetic chemistry. Key to this success has been the design of chiral ligands to control the regio-, diastereo-, and enantioselectivity. Phosphoramidites have emerged as a highly versatile and readily accessible class of chiral ligands. Their modular structure enables the formation of ligand libraries and easy fine-tuning for a specific catalytic reaction. Phosphoramidites frequently show exceptional levels of stereocontrol, and their monodentate nature is essential in combinatorial catalysis, where a ligand-mixture approach is used. In this Review, recent developments in asymmetric catalysis with phosphoramidites used as ligands are discussed, with a focus on the formation of carbon-carbon and carbon-heteroatom bonds.

Phosphoramidites: Privileged Ligands in Asymmetric Catalysis

Enantioselective allylic substitution reactions comprise some of the most versatile methods for preparing enantiomerically enriched materials. These reactions form products that contain multiple functionalities by creating carbon−nitrogen, carbon−oxygen, carbon−carbon, and carbon−sulfur bonds. For many years, the development of catalysts for allylic substitution focused on palladium complexes. However, studies of complexes of other metals have revealed selectivities that often complement those of palladium systems. Most striking is the observation that reactions with unsymmetrical allylic electrophiles that typically occur with palladium catalysts at the less hindered site of an allylic electrophile occur at the more hindered site with catalysts based on other metals. In this Account, we describe the combination of an iridium precursor and a phosphoramidite ligand that catalyzes enantioselective allylic substitution reactions with a particularly broad scope of nucleophiles. The active form of this iridium...

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Mechanistically Driven Development of Iridium Catalysts for Asymmetric Allylic Substitution

In this review, we summarize the origin and advancements of iridium-catalyzed asymmetric allylic substitution reactions during the past two decades. Since the first report in 1997, Ir-catalyzed asymmetric allylic substitution reactions have attracted intense attention due to their exceptionally high regio- and enantioselectivities. Ir-catalyzed asymmetric allylic substitution reactions have been significantly developed in recent years in many respects, including ligand development, mechanistic understanding, substrate scope, and application in the synthesis of complex functional molecules. In this review, an explicit outline of ligands, mechanism, scope of nucleophiles, and applications is presented.

Iridium-Catalyzed Asymmetric Allylic Substitution Reactions

Iridium-catalysed asymmetric allylic substitutions.

Regio‐ and Enantioselective Iridium‐Catalyzed Allylic Alkylation with In Situ Activated P,C‐Chelate Complexes

https://www.rsc.org/suppdata/cc/b5/b503713a/b503713a.pdf

Carbocycles via enantioselective inter- and intramolecular iridium-catalysed allylic alkylations

Regio‐ und enantioselektive Iridium‐katalysierte allylische Alkylierung mit in situ aktivierten P,C‐Chelatkomplexen

Simplified procedures for the Ir-catalyzed asymmetric allylic alkylation reaction are described that often allow substitution products to be obtained with ≥99% ee. Applications to syntheses of important chiral building blocks, such as the Taniguchi lactone and dimethyl 2-vinylcyclopropane-1,1 -dicarboxylate, are presented.

Enantioselective Iridium-Catalyzed Allylic Alkylations - Improvements and Applications Based on Salt-Free Reaction Conditions

Iridium-catalyzed aminations of allylic carbonates containing a variety of O-functional groups have been explored. High degrees of regio- as well as enantioselectivity were achieved with diacylamides under salt-free conditions and with arylamines. The results allowed the antiepilepsy drug (S)-vigabatrin to be prepared via a very short route.

Enantioselective Iridium-CatalyzedAllylic Aminations of Allylic Carbonates with Functionalized SideChains. Asymmetric Total Synthesis of (S)-Vigabatrin

Nicole Miller

Papers

Regio‐ and Enantioselective Iridium‐Catalyzed Allylic Alkylation with In Situ Activated P,C‐Chelate Complexes

Carbocycles via enantioselective inter- and intramolecular iridium-catalysed allylic alkylations

Regio‐ und enantioselektive Iridium‐katalysierte allylische Alkylierung mit in situ aktivierten P,C‐Chelatkomplexen

Enantioselective Iridium-Catalyzed Allylic Alkylations - Improvements and Applications Based on Salt-Free Reaction Conditions

Enantioselective Iridium-CatalyzedAllylic Aminations of Allylic Carbonates with Functionalized SideChains. Asymmetric Total Synthesis of (S)-Vigabatrin