Design and Application of New Pyridine-Derived Chiral Ligands in Asymmetric Catalysis

Accounts of Chemical Research, Journal Year: 2024, Volume and Issue: 57(6), P. 957 - 970

Published: March 6, 2024

ConspectusThe innovation of chiral ligands has been crucial for the asymmetric synthesis functional molecules, as demonstrated by several types widely applied "privileged" ligands. In this context, pyridine-derived ligands, far some oldest and most utilized in catalysis, have attracted considerable research interest past half-century. However, development broadly applicable pyridine units (CPUs) plagued intertwining challenges, thus delaying advancements many reactions.This Account aims to summarize recent progress new CPU-containing focusing on a rationally designed, modular, tunable CPU developed our laboratory. A significant problem thwarting conventional designs is paradox between broad reactivity stereoselectivity; that is, while enhanced stereoselectivity may be achieved introducing elements close N atom, concomitant increase local steric hindrance often limits catalytic activity scope. Our newly features rigid [6-5-3] fused-ring framework spirocyclic ketal side wall. The well-defined three-dimensional structure minimizes (inner layer) tunes peripheral environment (outer remote substituents, securing stereoselectivity. Different chelating were readily assembled using structural module, with applications mechanistically diverse transition-metal-catalyzed reactions. Thus, series 2,2′-bipyridine successfully employed general, efficient, highly enantioselective nickel-catalyzed intermolecular reductive addition, Ullmann coupling ortho-chlorinated aryl aldehydes, carboxylation benzylic (pseudo)halides CO2. Notably, these exhibited superior reactions compared common N-based iridium-catalyzed C–H borylation was N,B-bidentate ligand. Furthermore, challenging, additive-free, broad-scope transfer hydrogenative direct amination half-sandwich iridium catalyst supported N,C-bidentate excellent performance high stereoselectivity, which, when combined experimental computational mechanistic investigations, "double-layer control" design concept.Considering described herein should inspire creation novel catalysts drive

Language: Английский

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Bio-waste derived Ag/chitin nanocatalyst induces green and efficient N-alkylation of alcohols with amines via borrowing hydrogen strategy

Chemical Engineering Journal, Journal Year: 2025, Volume and Issue: unknown, P. 160587 - 160587

Published: Feb. 1, 2025

Language: Английский

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Persistent acyclic Cp*Ir(III) complexes and their reactivities in cross-coupling reactions

Nature Communications, Journal Year: 2025, Volume and Issue: 16(1)

Published: May 14, 2025

Iridium(III) complexes play a prominent role in organometallic chemistry, with significant research efforts directed toward Cp*Ir(III) species, broadly categorized into cyclic and acyclic types. Although studies on these two classes began roughly simultaneously, the development of has lagged significantly behind their counterparts. Herein, we report general efficient strategy for synthesizing various persistent aryl Cp*Ir(III)(CO)Cl directly from aldehydes, situ generated CO as stabilizing ligand. These showcase exceptional reactivity, undergoing reactions up to eight nucleophiles generate diverse diorganoiridium(III) species remarkable stability. Electrochemical analysis provides insights reductive elimination processes. Guided by findings, Cp*Ir(III)-mediated decarbonylative C-C C-O cross-couplings aldehydes are successfully developed. This study establishes robust platform exploration complexes, paving way further advancements iridium(III) chemistry.

Language: Английский

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Direct synthesis of chiral β-arylamines via additive-free asymmetric reductive amination enabled by tunable bulky phosphoramidite ligands

Chemical Science, Journal Year: 2024, Volume and Issue: 15(38), P. 15811 - 15818

Published: Jan. 1, 2024

An additive-free asymmetric reductive amination for efficient chiral β-arylamine synthesis is described. Bulky and tunable phosphoramidite ligands enable excellent enantiomeric control, even alkylamines which lack secondary coordinating sites.

Language: Английский

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Ir/XuPhos-Catalyzed Direct Asymmetric Reductive Amination of Ketones with Secondary Amines

Organic Chemistry Frontiers, Journal Year: 2024, Volume and Issue: 11(23), P. 6735 - 6741

Published: Jan. 1, 2024

We herein report a novel iridium catalyst with XuPhos as chiral monodentate phosphine ligand for the direct asymmetric reductive amination of ketones secondary amines, providing series tertiary amines efficiently.

Language: Английский

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