We Already Know Everything about Oxidative Addition to Pd(0): Do We?

ACS Catalysis, Journal Year: 2023, Volume and Issue: 13(17), P. 11399 - 11421

Published: Aug. 15, 2023

The oxidative addition (OA) of organic electrophiles to Pd(0) is a fundamental step in organopalladium chemistry and plays key role palladium-catalyzed cross-coupling reactions. This perspective summarizes selected mechanistic studies the Pd(0)-to-Pd(II) OA process involving halides pseudohalides with focus on systems relevant catalytic results are organized according nature supporting ligands, extracting general trends, describing most examples. formation active species from precatalysts surveyed, as well influence different that could be present under conditions process, providing guidelines facilitate understanding improvement

Language: Английский

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Mechanisms of Activating Agents to Form Organozinc Reagents from Zinc Metal: Lessons for Reaction Design

The Journal of Organic Chemistry, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 2, 2025

Activating agents enable the efficient preparation of organozinc complexes from zinc metal and organohalides, but their mechanisms had been obscured by heterogeneous nature these systems. Fluorescence microscopy, with sensitivity to detect surface reaction intermediates, reveals distinct activating widely used activation strategies: trimethylsilyl chloride, LiCl, DMSO, Rieke powder. The resulting development mechanistic models provides a better understanding oxidative-addition–solubilization sequence in reagent formation contains lessons for methods development.

Language: Английский

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Investigations of the Reaction of HB(pin) with Tris(amido) Y(III) Complexes

Organometallics, Journal Year: 2025, Volume and Issue: unknown

Published: April 22, 2025

Language: Английский

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Copper-Catalyzed Homocoupling of Boronic Acids: A Focus on B-to-Cu and Cu-to-Cu Transmetalations

Molecules, Journal Year: 2022, Volume and Issue: 27(21), P. 7517 - 7517

Published: Nov. 3, 2022

Controlling and understanding the Cu-catalyzed homocoupling reaction is crucial to prompt development of efficient cross-coupling reactions. The presence a coordinating base (hydroxide methoxide) enables B-to-Cu(II) transmetalation from aryl boronic acid CuIICl2 in methanol, through formation mixed Cu-(μ-OH)-B intermediates. A second B-to-Cu form bis-aryl Cu(II) complexes disfavored. Instead, organocopper(II) dimers undergo coupled transmetalation-electron transfer (TET) allowing bis-organocopper(III) readily promoting reductive elimination. Based on this mechanism some guidelines are suggested control undesired product

Language: Английский

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Factors controlling the structure of alkylzinc amidinates: on the role of N-substituents

Dalton Transactions, Journal Year: 2023, Volume and Issue: 52(9), P. 2712 - 2721

Published: Jan. 1, 2023

Despite various applications of alkylzinc complexes supported by N,N-bidentate ligands in chemistry and materials science, the corresponding organozinc amidinates still represent an insufficiently explored area. To gain a more in-depth understanding factors controlling structure stability amidinates, we selected benzamidinate N,N'-diphenylformamidinate as model N,N'-unsubstituted N,N'-diaryl substituted ligands, respectively, to systematically modify secondary coordination sphere Zn center. A series new has been synthesized their molecular structures identified both solid state (single-crystal X-ray crystallography) solution (NMR FTIR spectroscopy). The results indicate that [RZnL]x-type amidinate moieties are essentially unstable tend undergo Schlenk equilibria-mediated ligand scrambling leading thermodynamically stable non-stoichiometric [R2Zn3L4]- [R3Zn4L5]-type complexes. This process is significantly influenced noncovalent interactions well steric hindrance provided zinc-bounded alkyl groups N-substituents.

Language: Английский

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Computed vs Experimental Energy Barriers in Solution: Influence of the type of the density functional approximation.

Published: March 20, 2024

Mechanistic investigations at the Density Functional Theory (DFT) level of organic and organometallic reactions in solution are now broadly accessible routinely implemented to complement experimental investigations. The selection an appropriate functional among plethora developed ones is first challenge on way reliable energy barrier calculations. To provide guidelines for choice initial computational level, performances commonly used non-empirical (PBE, PBE0, PBE0-DH) empirical density functionals (BLYP, B3LYP, B2PLYP) were evaluated relative activation enthalpies. Most reactivity databases assess primarily based high calculations, here a set enthalpies performed selected from literature. As general trend, outperform ones. most accurate barriers obtained with hybride PBE0 double-hybrid PBE0-DH functionals, both providing similar performance. Regardless under consideration, addition GD3-BJ dispersion correction does not enhance accuracy computed barriers.

Language: Английский

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Computed versus experimental energy barriers in solution: Influence of the type of the density functional approximation

Journal of Computational Chemistry, Journal Year: 2024, Volume and Issue: 45(27), P. 2284 - 2293

Published: June 7, 2024

Mechanistic investigations at the density functional theory level of organic and organometallic reactions in solution are now broadly accessible routinely implemented to complement experimental investigations. The selection an appropriate among plethora developed ones is first challenge on way reliable energy barrier calculations. To provide guidelines for choice initial computational level, performances commonly used non-empirical (PBE, PBE0, PBE0-DH) empirical functionals (BLYP, B3LYP, B2PLYP) were evaluated relative activation enthalpies. Most reactivity databases assess primarily based high calculations, here a set enthalpies performed selected from literature. As general trend, outperform ones. most accurate barriers obtained with hybrid PBE0 double-hybrid PBE0-DH functionals, both providing similar performance. Regardless under consideration, addition GD3-BJ dispersion correction does not enhance accuracy computed barriers.

Language: Английский

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The Mechanism of Lithium Zincate‐Mediated I/Zn Exchange Revisited: A Computational Microsolvation Approach in THF**

European Journal of Organic Chemistry, Journal Year: 2023, Volume and Issue: 26(43)

Published: Oct. 6, 2023

Abstract Lithium trialkylzincate‐mediated I/Zn exchange reaction has been revisited computationally through a microsolvation approach. A never yet investigated iodoaryl derivative bearing potential bulky para ‐directing group, namely 4‐iodobenzyl mesylate, was considered as substrate. THF typical solvent and Et 3 ZnLi have also for the first time in such reaction. Three mechanistic pathways calculated, including (1) literature‐inspired pathway with full preservation of synergic character reagent well complementary mesylate group‐directed pathway, (2) THF‐solvated open complex‐promoted (3) an anionic pathway. While appeared to be unlikely, involving zincate complex turned out most energetically favored. Equivalent thermodynamic profiles were found both reagent, albeit slight preference could attributed that occurring initial chelation Li group (OMs) The shown proceed lithium‐assisted aryl shuttle‐like process. substrate is converted into ArLi intermediate which turns reacts remaining diorganozinc reagent.

Language: Английский

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Copper-Catalyzed Homocoupling of Boronic Acids: A focus on B-to-Cu and Cu-to-Cu Transmetalations

Published: Oct. 10, 2022

Controlling and understanding Cu-catalyzed homocoupling reaction is crucial to prompt the development of efficient cross-coupling reactions. The presence a coordinating base (hydroxide, methoxide) enables B-to-Cu(II) transmetalation from aryl boronic acid CuIICl2 in methanol, through formation mixed Cu-(μ-OH)-B intermediates. A second B-to-Cu form bis-aryl Cu(II) complexes disfavored. Instead, organocopper(II) dimers undergo coupled transmetalation-electron-transfer (TET) allowing bis-organocopper(III) readily promoting reductive elimination. Based on this mechanism some guidelines are suggested control undesired product

Language: Английский

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Zn/F carbenoids: preparation, structures, stability, and application to nucleophilic monofluoroalkylation

Organic Chemistry Frontiers, Journal Year: 2024, Volume and Issue: 11(15), P. 4194 - 4206

Published: Jan. 1, 2024

We described here comprehensive studies on Zn/F carbenoids. carbenoids were found to be stable and useful nucleophilic monofluoroalkylating reagents, providing a new synthetic route functionalized monofluroalkanes.

Language: Английский

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