Stereodivergent Synthesis of Allenes with α,β‐Adjacent Central Chiralities Empowered by Synergistic Pd/Cu Catalysis

Angewandte Chemie International Edition, Год журнала: 2023, Номер 62(9)

Опубликована: Янв. 3, 2023

The stereodivergent synthesis of allene compounds bearing α,β-adjacent central chiralities has been realized via the Pd/Cu-catalyzed dynamic kinetic asymmetric alkylation racemic allenylic esters. matched reactivity bimetallic catalytic system enables challenging reaction aryl-substituted acetates with sterically crowded aldimine esters smoothly under mild conditions. Various chiral non-natural amino acids a terminal allenyl group are easily synthesized in high yields and excellent diastereo- enantioselectivities (up to >20 : 1 dr, >99 % ee). Importantly, all four stereoisomers product can be readily accessed by switching configurations two metal catalysts. Furthermore, easy interconversion between uncommon η3 -butadienyl palladium intermediate featuring weak C=C/Pd coordination bond stable Csp2 -Pd is beneficial for transformation process (DyKAT).

Язык: Английский

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Synergistic Pd/Cu-Catalyzed 1,5-Double Chiral Inductions

Journal of the American Chemical Society, Год журнала: 2024, Номер 146(13), С. 9241 - 9251

Опубликована: Март 19, 2024

Much attention has been focused on the catalytic asymmetric creation of single chiral centers or two adjacent stereocenters. However, construction nonadjacent stereocenters is significant importance but challenging because lack remote induction models. Herein, based a C═C bond relay strategy, we report synergistic Pd/Cu-catalyzed 1,5-double model. All four stereoisomers target products bearing 1,5-nonadjacent involving both allenyl axial and central chirality could be obtained divergently by simply changing combination catalysts with different configurations. Control experiments DFT calculations reveal novel mechanism 1,5-oxidative addition, contra-thermodynamic η3-allyl palladium shift, conjugate nucleophilic substitution, which play crucial roles in control reactivity, regio-, enantio-, diastereoselectivity. It expected that this strategy may provide general protocol for synthesis structural motifs distant

Язык: Английский

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Synergistic Pd/Cu Catalysis in Organic Synthesis

Chemistry - A European Journal, Год журнала: 2019, Номер 26(22), С. 4895 - 4916

Опубликована: Ноя. 25, 2019

Synergistic Pd/Cu catalysis has been utilized in the Sonogashira reaction since 1975. However, this strategy not received much attention from organic chemist community until recently. is becoming a proficient method for development of catalytic reactions, including several new and efficient cross-coupling reactions. Additionally, challenging asymmetric stereodivergent synthesis, have discovered by combined use chiral metal catalyst second achiral or two catalysts. This review provides an overview field, with aims highlighting both synergistic synthesis mechanisms involved research area.

Язык: Английский

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Asymmetric Decarboxylative Cycloaddition of Vinylethylene Carbonates with β-Nitroolefins by Cooperative Catalysis of Palladium Complex and Squaramide

ACS Catalysis, Год журнала: 2018, Номер 8(12), С. 11600 - 11604

Опубликована: Ноя. 2, 2018

An efficient method for the enantio- and diastereoselective construction of multisubstituted tetrahydrofurans via asymmetric decarboxylative cycloaddition vinylethylene carbonates with β-nitroolefins under a cooperative catalysis palladium complex squaramide is developed. By using generated in situ from Pd2(dba)3·CHCl3 phosphoramidite L1 chiral OC4 as catalysts mild conditions, process provided bearing quaternary stereocenter good to high yields acceptably diastereoselectivities.

Язык: Английский

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Palladium‐Catalyzed Asymmetric [8+2] Dipolar Cycloadditions of Vinyl Carbamates and Photogenerated Ketenes

Angewandte Chemie International Edition, Год журнала: 2020, Номер 59(33), С. 14096 - 14100

Опубликована: Май 6, 2020

Higher-order cycloadditions, particularly [8+2] are a straightforward and efficient strategy for constructing significant medium-sized architectures. Typically, configuration-restrained conjugated systems utilized as 8π-components higher-order concerted cycloadditions. However, this reason, 10-membered monocyclic skeletons have never been constructed via catalytic asymmetric cycloaddition with high peri- stereoselectivity. Here, we accomplished an enantioselective dipolar the merger of visible-light activation palladium catalysis. This protocol provides new route to architectures bearing chiral quaternary stereocenters chemo-, peri-, enantioselectivity. The success relied on facile in situ generation Pd-containing 1,8-dipoles their trapping by ketene dipolarophiles, which were formed photo-Wolff rearrangement.

Язык: Английский

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Stereodivergent Synthesis of Enantioenriched 2,3-Disubstituted Dihydrobenzofurans via a One-Pot C–H Functionalization/Oxa-Michael Addition Cascade

Journal of the American Chemical Society, Год журнала: 2021, Номер 143(23), С. 8583 - 8589

Опубликована: Июнь 1, 2021

A one-pot rhodium-catalyzed C–H functionalization/organocatalyzed oxa-Michael addition cascade reaction has been developed. This methodology enables the stereodivergent synthesis of diverse 2,3-disubstituted dihydrobenzofurans with broad functional group compatibility in good yields high levels stereoselectivity under exceptionally mild conditions. The full complement stereoisomers chiral and 3,4-disubstituted isochromans could be accessed at will by appropriate permutations two catalysts. current work provides a rare example catalysts independently controlling contiguous stereogenic centers subsequently via two-step single operation.

Язык: Английский

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Reductive Allylic Defluorinative Cross-Coupling Enabled by Ni/Ti Cooperative Catalysis

Organic Letters, Год журнала: 2019, Номер 21(20), С. 8316 - 8322

Опубликована: Окт. 1, 2019

Unactivated alkyl chlorides are abundant building blocks in organic synthesis, but they have been rarely engaged cross-electrophile coupling. Herein, we report a Ni/Ti-cocatalyzed reductive allylic defluorinative cross-coupling between trifluoromethyl alkenes and unactivated bromides, enabling the efficient preparation of diverse functional-group-rich gem-difluoroalkenes. Notably, synthesis gem-difluoroalkene analogues azaperone, haloperidol, benperidol was also accomplished using our method as key step.

Язык: Английский

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Catalytic asymmetric synthesis of monofluoroalkenes and gem-difluoroalkenes: advances and perspectives

Organic Chemistry Frontiers, Год журнала: 2021, Номер 8(10), С. 2315 - 2327

Опубликована: Янв. 1, 2021

The latest achievements in the catalytic asymmetric synthesis of both monofluoro- and gem-difluoroalkenes are discussed.

Язык: Английский

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Cooperative Ni/Cu‐Catalyzed Asymmetric Propargylic Alkylation of Aldimine Esters

Angewandte Chemie International Edition, Год журнала: 2020, Номер 59(34), С. 14270 - 14274

Опубликована: Май 18, 2020

A novel Ni/Cu dual catalysis gives rise to fundamentally new cooperative reactivity and enables the regio- enantioselective propargylic alkylation reaction. diverse set of α-quaternary propargylated amino ester derivatives were synthesized in good yields with excellent enantioselectivity (up 99 % ee). This work highlights power catalysis, which can be expected have broad implications homogeneous beyond highly valuable synthetic intermediates.

Язык: Английский

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Ternary Catalysis Enabled Three-Component Asymmetric Allylic Alkylation as a Concise Track to Chiral α,α-Disubstituted Ketones

Journal of the American Chemical Society, Год журнала: 2021, Номер 143(49), С. 20818 - 20827

Опубликована: Дек. 6, 2021

Multicomponent reactions that involve interception of onium ylides through Aldol, Mannich, and Michael addition with corresponding bench-stable acceptors have demonstrated broad applications in synthetic chemistry. However, because the high reactivity transient survival these situ generated intermediates, substitution-type process, especially asymmetric catalytic version, remains hitherto unknown. Herein, a three-component allylation α-diazo carbonyl compounds alcohols allyl carbonates is disclosed by employing ternary cooperative catalysis achiral Pd-complex, Rh2(OAc)4, chiral phosphoric acid CPA. This method represents first example allylic alkylation an SN1-type trapping which involves convergent assembly two active Pd-allyl species, enol derived from ylides, providing expeditious access to α,α-disubstituted ketones good yields excellent enantioselectivity. Combined experimental computational studies shed light on mechanism this novel reaction, including critical role Xantphos ligand origin

Язык: Английский

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