Transition Metal-Catalyzed Asymmetric Migratory Allylic C—H Functionalization of Remote Dienes

Chinese Journal of Organic Chemistry, Journal Year: 2025, Volume and Issue: 45(2), P. 592 - 592

Published: Jan. 1, 2025

Language: Английский

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Chemodivergent Tandem Hydroalkylation and Hydroalkenoxylation of Conjugated Enynes

ACS Catalysis, Journal Year: 2024, Volume and Issue: 14(13), P. 9742 - 9751

Published: June 14, 2024

Due to the instability and weak O-nucleophilicity of enol, carbonyl compounds prefer function as C-nucleophiles instead O-nucleophiles in extensively studied transition metal-catalyzed hydrofunctionalizations unsaturated bonds. The corresponding hydroalkenoxylation reaction has thus long been unexplored. Here, we describe a chemodivergent protocol for challenging reactions. Dictated by Pd catalyst bearing different ligands, both 5-exo-trig 6-endo-trig processes are demonstrated be feasible between 1,3-enynes ketoesters, polysubstituted hydrofurans hydropyrans achieved good yields excellent chemoselectivities. In addition, enantioselective is also explored under an Rh moderate efficiency but with high stereoselectivities. Mechanistic studies corroborate designed tandem hydroalkylation uncover that ligand-to-ligand hydrogen transfer process might involved turnover-limiting step hydroalkenoxylation.

Language: Английский

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Asymmetric formal sp2-hydrocarbonations of dienes and alkynes via palladium hydride catalysis

Nature Communications, Journal Year: 2023, Volume and Issue: 14(1)

Published: Oct. 9, 2023

Abstract Transition metal-catalyzed asymmetric hydrofunctionalizations of unsaturated bonds via π-ƞ 3 substitution have emerged as a reliable method to construct stereogenic centers, and mainly rely on the use heteroatom-based or carbon nucleophiles bearing acidic C-H bonds. In comparison, sp 2 are generally not under consideration because enormous challenges in cleaving corresponding inert Here, we report protocol achieve formal hydrocarbonations, including hydroalkenylation, hydroallenylation hydroketenimination both 1,3-dienes alkynes hydroalkylation Wittig reaction cascade. A series unachievable motifs hydrofunctionalizations, such di-, tri- tetra-substituted alkenes, allenes, tri-substituted ketenimines allyl skeletons all facilely constructed high regio-, diastereo- enantioselectivities with this cascade design. Stereodivergent synthesis four stereoisomers 1,4-diene stereocenter Z/E-controllable olefin unit highlights power present protocol. An interesting mechanistic feature is revealed that alkyne actually undergoes hydrocarbonation formation conjugated diene intermediate, different from conventional viewpoint hydrofunctionalization only involves allene species.

Language: Английский

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Nickel-catalyzed direct stereoselective α-allylation of ketones with non-conjugated dienes

Nature Communications, Journal Year: 2023, Volume and Issue: 14(1)

Published: Nov. 22, 2023

The development of efficient and sustainable methods for the construction carbon-carbon bonds with simultaneous stereoselective generation vicinal stereogenic centers is a longstanding goal in organic chemistry. Low-valent nickel(0) complexes which promote α-functionalization carbonyls leveraging its pro-nucleophilic character conjunction suitable olefin acceptors are scarce. We report Ni(0)NHC catalyst selectively converts ketones non-conjugated dienes to synthetically highly valuable α-allylated products. directly activates α-hydrogen atom carbonyl substrate transferring it acceptor. transformation creates adjacent quaternary tertiary diastereoselective enantioselective manner. Computational studies indicate ability trigger ligand-to-ligand hydrogen transfer process from ketone substrate, setting selectivity process. shown selective functionalization α-C-H bond groups by opens up new opportunities exploit 3d-metal catalysis access chiral building blocks.

Language: Английский

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Synthesis of Allenes by Hydroalkylation of 1,3-Enynes with Ketones Enabled by Cooperative Catalysis

Journal of the American Chemical Society, Journal Year: 2023, Volume and Issue: 145(39), P. 21638 - 21645

Published: Sept. 22, 2023

A method for the synthesis of allenes by addition ketones to 1,3-enynes cooperative Pd(0)Senphos/B(C6F5)3/NR3 catalysis is described. wide range aryl- and aliphatic undergo various in high yields at room temperature. Mechanistic investigations revealed a rate-determining outer-sphere proton transfer mechanism, which was corroborated DFT calculations.

Language: Английский

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Palladium-Catalyzed Asymmetric O-1,5-Addition with Oximes via Hydroximation of Unsaturated Esters

Organic Letters, Journal Year: 2023, Volume and Issue: 26(1), P. 89 - 93

Published: Dec. 21, 2023

Different from electronically matched 1,4- and 1,6-additions, herein, we disclose an mismatched 1,5-conjugate addition process with oximes as the nucleophiles. By this design, oxime moieties are readily introduced to γ-position of electron-deficient substrates in good yields, excellent regioselectivities, high enantioselectivities. The corresponding allyl also conveniently transformed into a series valuable enantioenriched skeletons.

Language: Английский

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Stereoselective Synthesis of Polysubstituted Dihydropyrroles via 1,5‐Addition and N‐1,4‐Addition Cascade

Chemistry - A European Journal, Journal Year: 2024, Volume and Issue: 30(38)

Published: May 3, 2024

An unprecedented 1,5-addition/N-1,4-addition cascade reaction is established via palladium hydride catalysis. A variety of polysubstituted dihydropyrrole skeletons are constructed in high yield and with exclusively >20 : 1 diastereoselectivity. enantioselective protocol this design also developed to provide a novel access enantioenriched dihydropyrroles.

Language: Английский

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Palladium‐Catalyzed Enantioselective Migratory Hydroamidocarbonylation of Amide‐Linked Alkenes to Access Chiral α‐Alkyl Succinimides

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: unknown

Published: July 15, 2024

A Pd-catalyzed asymmetric isomerization-hydroamidocarbonylation of amide-containing alkenes was developed, affording a variety chiral α-alkyl succinimides in moderate to good yields with high enantioselectivities. The key success introducing bulky 1-adamentyl P-substitution and 2,3,5,6-tetramethoxyphenyl group into the rigid P-chirogenic bisphosphine ligand create stronger steric hinderance deeper catalytic pocket. By this approach, regio- or stereo-convergent synthesis enantiomeric from mixture olefin isomers achieved.

Language: Английский

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Diastereoselective and Enantioselective Hydrophosphinylations of Conjugated Enynes, Allenes and Dienes via Synergistic Pd/Co Catalysis

Angewandte Chemie, Journal Year: 2024, Volume and Issue: 137(1)

Published: Sept. 10, 2024

Abstract Different from the reported work focusing on construction of single P ‐ or C ‐stereocenter via hydrophosphinylation unsaturated carbon bonds, highly diastereo‐ and enantioselective reaction allenes, conjugated enynes 1,3‐dienes is achieved a designed Pd/Co dual catalysis newly modified masked phosphinylating reagent. A series allyl motifs bearing both tertiary are prepared in generally good yields, >20 : 1 dr, rr 99 % ee. The unprecedented 1,3‐enynes established to generate skeletons containing nonadjacent chiral axis. first stereodivergent also developed achieve all four ‐containing stereoisomers. present protocol features use only 3‐minutes time 0.1 catalyst, with observation up 730 TON. set mechanistic studies reveal necessity roles two metal catalysts corroborate synergistic process.

Language: Английский

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Stereodivergent 1,5-Conjugate Addition with Iminoesters via Pd/Cu Dual Catalysis

Synthesis, Journal Year: 2023, Volume and Issue: 56(22), P. 3412 - 3420

Published: Dec. 15, 2023

Abstract The first stereodivergent umpolung 1,5-conjugate addition reaction via synergistic Pd/Cu catalysts is reported. By dictating the absolute configuration of each chiral ligand ligated to corresponding metals, all four stereoisomers products are easily achieved. A series amino acid moieties introduced γ-position conjugated esters in high yields with excellent diastereoselectivities and enantioselectivities. downstream transformations highlight synthetic value method.

Language: Английский

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