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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Palladium-catalyzed (Z)-selective allylation of phosphine oxides with vinylethylene carbonates to construct phosphorus allyl alcohols

Organic & Biomolecular Chemistry, Journal Year: 2024, Volume and Issue: 22(15), P. 3068 - 3072

Published: Jan. 1, 2024

Allylphosphine oxide compounds are important building blocks with broad applications in organic synthesis and pharmaceutical science. Herein, we report an unprecedented palladium-catalyzed allylation of phosphine oxides vinylethylene carbonates, producing various phosphorus allyl alcohols excellent yields high

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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Studies on the [4 + 2] cycloaddition and allylic substitution of indole-fused zwitterionic π-allylpalladium

Organic & Biomolecular Chemistry, Journal Year: 2023, Volume and Issue: 21(40), P. 8162 - 8169

Published: Jan. 1, 2023

The zwitterionic π-allylpalladium species, also known as dipoles, are important synthons widely used in various reactions including cycloaddition and allylic substitution. This study reported the development of a new indole-fused precursor compound its application [4 + 2] substitution reactions. As result, synthesis pyrrolo[3,2,1-ij]quinazolin-3-one 7-vinyl indole compounds was achieved with moderate to good yields. Notably, reaction exhibited excellent regio- stereoselectivity.

Language: Английский

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Rhodium-Catalyzed Enantioselective Ring-Openings of Oxabicyclic Alkenes with Azole Nucleophiles

The Journal of Organic Chemistry, Journal Year: 2024, Volume and Issue: 89(22), P. 16889 - 16898

Published: Nov. 6, 2024

We report enantioselective ring-openings of oxabicyclic alkenes with azole nucleophiles, generating heterocycle-bearing dihydronaphthalene products. Pyrazoles, triazoles, tetrazoles, and benzo-fused derivatives participate in the ring-opening, level regioselectivity depending on type substitution pattern heterocyclic partner. Electron-withdrawing substituents have a beneficial effect, suppressing unproductive complexation nitrogen Rh(I)-bis(phosphine) catalyst.

Language: Английский

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Pd‐Catalyzed Allylic Substitution using Nucleophilic Amines: Access to Functionalized Mono‐ and Bis‐N‐Allyl Synthons

Advanced Synthesis & Catalysis, Journal Year: 2024, Volume and Issue: 366(22), P. 4709 - 4714

Published: Aug. 10, 2024

Abstract We here report a catalytic strategy to enable the decarboxylative allylic amination of vinyl cyclic carbonates using various aliphatic and nucleophilic amines. The use protic medium chelating diphosphine ligands are main drivers towards chemoselective amine formation, thereby minimizing undesired ligand‐driven complex speciation aminolysis involved substrate. This improved approach amplifies repertoire synthons that can be prepared from variety substrate combinations.

Language: Английский

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Five-membered ring systems: with more than one N atom

Progress in heterocyclic chemistry, Journal Year: 2023, Volume and Issue: unknown, P. 281 - 332

Published: Jan. 1, 2023

Language: Английский

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Stereoselective Synthesis of Tri- and Tetrasubstituted Allylsilanes via Copper-Catalyzed Decarboxylative Silylation of Vinylethylene Carbonates

The Journal of Organic Chemistry, Journal Year: 2023, Volume and Issue: 88(24), P. 16797 - 16802

Published: Nov. 27, 2023

Herein, a stereoselective copper-catalyzed decarboxylative silylation of readily available vinylethylene carbonates (VECs) with PhMe2Si-Bpin is reported, affording wide range tri- and tetrasubstituted allylsilanes in moderate to high yields E-selectivity. This protocol was characterized by stereoselectivity, broad substrate scope, operational simplicity, mild reaction conditions, which were amenable diverse derivatizations gram-scale synthesis.

Language: Английский

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