Synergistic Organoboron/Palladium Catalysis for Regioselective N-Allylations of Azoles with Allylic Alcohols

Organic Letters, Journal Year: 2022, Volume and Issue: 24(41), P. 7617 - 7621

Published: Oct. 6, 2022

A method for regioselective palladium-catalyzed allylic alkylation of ambident nitrogen heterocycles, employing simple alcohols as electrophile precursors, is described. An organoboron co-catalyst serves both to activate the azole-type nucleophile toward selective N-functionalization and accelerate formation a π-allylpalladium complex from alcohol. The can be applied various heterocycle types, including 1,2,3- 1,2,4-triazoles, tetrazoles, pyrazoles, purines, extended substituted alcohol partners.

Language: Английский

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Origins of Regioselectivity in CuH-Catalyzed Hydrofunctionalization of Alkenes

The Journal of Organic Chemistry, Journal Year: 2023, Volume and Issue: 88(5), P. 2750 - 2757

Published: Feb. 15, 2023

Factors controlling the regioselectivity in alkene hydrocupration were computationally investigated using energy decomposition analysis. The results demonstrate that Markovnikov-selective with electronically activated mono-substituted olefins is mostly affected by destabilizing Pauli repulsion, which due to electron delocalization effect. anti-Markovnikov-selective 1,1-dialkyl-substituted terminal dominated repulsive electrostatic interactions, because of unequal π distribution caused induction effect alkyl substituents.

Language: Английский

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Mechanism of palladium-catalyzed allylic substitution of tertiary allylic carbonates with sodium sulfinates: unusual bifunctional nucleophile-enabled inner-sphere pathway and origin of regio- and enantioselectivities

Catalysis Science & Technology, Journal Year: 2024, Volume and Issue: 14(6), P. 1642 - 1652

Published: Jan. 1, 2024

DFT calculations were performed to investigate Pd-catalyzed allylic sulfonylation of tertiary carbonates. The bifunctional role the sulfonate nucleophile enables C–S bond formation via a unique inner-sphere pathway.

Language: Английский

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Computational insights into the synergistic interplay of ligand and fluorine effects in palladium-catalyzed regiodivergent decarboxylative allylic alkylation

Organic Chemistry Frontiers, Journal Year: 2024, Volume and Issue: 11(10), P. 2870 - 2883

Published: Jan. 1, 2024

DFT calculations were performed to investigate palladium-catalyzed decarboxylative allylic alkylation of allyl difluoro-β-ketoesters. The synergistic effects ligand and fluorine substituents on regioselectivity uncovered.

Language: Английский

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A computational study on cobalt-catalyzed allylic substitution of racemic allylic carbonates with amines: inner-sphere C–N reductive elimination and origins of regio- and enantioselectivities

Organic Chemistry Frontiers, Journal Year: 2023, Volume and Issue: 10(12), P. 2976 - 2987

Published: Jan. 1, 2023

DFT calculations reveal an inner-sphere C–N reductive elimination pathway for the cobalt/bisoxazolinephosphine-catalyzed allylic substitution of racemic carbonates with amines.

Language: Английский

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Synergistic Organoboron/Palladium Cocatalyzed Dehydrative Couplings of Azoles with Allylic Alcohols: A Combined Experimental and Computational Mechanistic Investigation

ACS Catalysis, Journal Year: 2024, Volume and Issue: 14(9), P. 6728 - 6739

Published: April 16, 2024

In the presence of Pd(Xantphos) and an electron-deficient arylboronic acid cocatalyst, azoles such as pyrazoles, triazoles, tetrazoles, purines undergo regioselective, dehydrative allylations with allylic alcohols. The boronic has a significant effect on both rate regioselectivity these reactions. Herein, combined experimental computational mechanistic study synergistic organoboron- palladium-catalyzed allylation is described. Kinetic analysis evaluation effects substitution reaction point toward turnover-limiting ionization alcohol, Lewis activation by acid. Computational modeling pathway density functional theory indicates that alcohol also regioselectivity-determining step resulting ion pair undergoes C–N bond formation through outer-sphere mechanism. An unexpected observation autocatalysis emerged from kinetic motivated additives, leading to development improved protocol.

Language: Английский

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Lone Pair−π Interactions in Organic Reactions

Chemical Reviews, Journal Year: 2024, Volume and Issue: unknown

Published: Nov. 13, 2024

Noncovalent interactions between a lone pair of electrons and π systems can be categorized into two types based on the nature systems. Lone pair-π(C═O) with unsaturated, polarized bonds are primarily attributed to orbital interactions, whereas pair-π(Ar) aromatic functional groups result from electrostatic attractions (for electron-deficient aryls) or dispersion Pauli repulsions electron-rich/neutral aryls). Unlike well-established noncovalent pair-π have been comparatively underappreciated less used influence reaction outcomes. This review emphasizes experimental computational studies aimed at integrating design catalytic utilizing these regulate reactivity selectivity chemical transformations. The role is highlighted in stabilization destabilization transition states ground-state binding. Examples influenced by both rings as included. At variance previous reviews, present not structured according physical origin particular classes but divided chapters ways which affect kinetics and/or reactions.

Language: Английский

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Palladium‐ and Iridium‐Catalyzed Deracemization of Allylic Oxygen Compounds with Oxygen Nucleophiles

European Journal of Organic Chemistry, Journal Year: 2022, Volume and Issue: 2022(44)

Published: Oct. 17, 2022

Abstract Allylic oxygen compounds (AOCs) are an important class of versatile building blocks in natural and non‐natural product synthesis. Catalytic in‐situ deracemization is attractive means for their enantioselective Particularly the AOCs through transition metal‐catalyzed dynamic kinetic asymmetric transformation (DYKAT) with nucleophiles (ONus). This review describes pertinent aspects palladium‐catalyzed DYKAT racemic allylic carboxylates, vinyl oxiranes dioxolanones hydrogen carbonate, alcohols, phenols, oximes, diosphenols water iridium‐catalyzed imidates carboxylates alcohols carboxylic acids. Included discussion desymmetrization meso ‐cycloalkene bis(carboxylates) carbonate. While Trost's bisphosphinobenzamides, Zhou's spiro‐phosphoramidite Feringa's BINOL‐phosphoramidite highly efficient ligands DYKAT, Carreira‐Dorta's BINOL‐phosphoramidite‐olefin excellent ligand DYKAT. also discusses mechanistic structural η 3 ‐allylpalladium‐bisphosphinobenzamide ‐allyliridium‐BINOL‐phosphoramidite‐olefin complexes corresponding catalysts.

Language: Английский

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Mechanistic Insights into the Palladium-Catalyzed Perfluoroalkylative Carbonylation of Unactivated Alkenes to β-Perfluoroalkyl Esters: A DFT Study

The Journal of Physical Chemistry A, Journal Year: 2024, Volume and Issue: 128(19), P. 3777 - 3783

Published: May 1, 2024

Transition metal-catalyzed multicomponent carbonylation is an efficient synthetic strategy to access multifunctional esters in high yields with broad functional group tolerance and good chemoselectivity. Considering the development of highly methods for esters, it remains significant grasp mechanism constructing esters. Herein, density theoretical calculations were carried out acquire mechanistic insight into synthesis β-perfluoroalkyl from a specific palladium-catalyzed perfluoroalkylative unactivated alkenes using carbon monoxide. A detailed understanding this reaction route includes (1) multistep radical process, (2) C–C coupling CO insertion, (3) ligand exchange, (4) Pd-based intermediate oxidation reductive elimination. The process was fundamentally rationalized, including Rf· formation radicals E alkene oxidation, respectively. potential energy calculation indicated that insertion perfluorinated alkyl preceded Pd-catalyzed competitively free process. In addition, I–/PhO– exchange step predicted be spontaneous products. IGMH analysis further attested elimination involved rate-determining step. Thus, simple valid theory (DFT) approach developed reveal

Language: Английский

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DFT mechanistic study on the synthesis of 2-fluorinated allylic scaffolds via PdII-catalyzed defluorinative arylation of gem-difluorocyclopropanes with phenylboronic acids

Molecular Catalysis, Journal Year: 2024, Volume and Issue: 562, P. 114194 - 114194

Published: May 8, 2024

Language: Английский

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