Identification of a Nitrenoid Reductive Elimination Pathway in Nickel-Catalyzed C–N Cross-Coupling

ACS Catalysis ◽  
2022 ◽  
pp. 1475-1480
Author(s):  
Connor M. Simon ◽  
Samantha L. Dudra ◽  
Ryan T. McGuire ◽  
Michael J. Ferguson ◽  
Erin R. Johnson ◽  
...  
Keyword(s):  
Cross Coupling ◽  
Reductive Elimination ◽  
Elimination Pathway

S(IV)–Mediated Unsymmetrical Heterocycle Cross-Couplings

2019 ◽  
Author(s):  
Min Zhou ◽  
Jet Tsien ◽  
Tian Qin
Keyword(s):  
Cross Coupling ◽  
Reductive Elimination ◽  
Facile Synthesis ◽  
Trigonal Bipyramidal

<p>Herein we report a sulfur (IV) mediated cross-coupling for facile synthesis of heteroaromatic substrates. Addition of heteroaryl nucleophiles onto a simple, readily-accessible alkyl sulfinyl (IV) chloride allows formation of a trigonal bipyramidal sulfurane intermediate. Reductive elimination therefrom provides bis-heteroaryl products in a practical and efficient fashion. <br></p>

Carbon-Heteroatom Cross-Coupling via an Electronically Excited Nickel (II) Complex

2019 ◽  
Author(s):  
Randolph Escobar ◽  
Jeffrey Johannes
Keyword(s):  
Energy Transfer ◽  
Functional Groups ◽  
Cross Coupling ◽  
Reductive Elimination ◽  
Aryl Halides ◽  
Coupling Reactions ◽  
General Methodology ◽  
Cross Coupling Reactions ◽  
Electronically Excited ◽  
Energy Transfer Pathway

<div>While carbon-heteroatom cross coupling reactions have been extensively studied, many methods are specific and</div><div>limited to a set of substrates or functional groups. Reported here is a method that allows for C-O, C-N and C-S cross coupling reactions under one general methodology. We propose that an energy transfer pathway, in which an iridium photosensitizer produces an excited nickel (II) complex, is responsible for the key reductive elimination step that couples aryl halides to 1° and 2° alcohols, anilines, thiophenols, carbamates and sulfonamides.</div>

Ni(COD)(DMFU): A Heteroleptic 16-Electron Precatalyst for 1,2-Diarylation of Alkenes

Synlett ◽  
2021 ◽  
Author(s):  
Nana Kim ◽  
Van T. Tran ◽  
Omar Apolinar ◽  
Steven Wisniewski ◽  
Martin Eastgate ◽  
...  
Keyword(s):  
Nickel Complex ◽  
Active Catalyst ◽  
Cross Coupling ◽  
Reductive Elimination ◽  
Coupling Reactions ◽  
Beneficial Effects ◽  
Cross Coupling Reactions ◽  
Growing Body ◽  
Hydride Elimination

Electron-deficient olefin (EDO) ligands are known to promote a variety of nickel-catalyzed cross-coupling reactions, presumably by accelerating the reductive elimination step and preventing undesired β-hydride elimination. While there is a growing body of experimental and computational evidence elucidating the beneficial effects of EDO ligands, significant gaps remain in our understanding of the underlying coordination chemistry of the Ni–EDO species involved. In particular, most procedures rely on in situ assembly of the active catalyst, and there is a paucity of pre-ligated Ni-EDO precatalysts. Herein, we investigate the 16-electron, heteroleptic nickel complex, Ni(COD)(DMFU), and examine the performance of this complex as a precatalyst in 1,2-diarylation of alkenes.

scholarly journals DFT Study of Unstrained Ketone C-C Bond Activation via Rhodium(I)-Catalyzed Suzuki-Miyaura Cross-Coupling Reactions

2019 ◽  
Author(s):  
Dengmengfei Xiao ◽  
Lili Zhao ◽  
Diego Andrada
Keyword(s):  
Density Functional ◽  
Bond Activation ◽  
Chemical Reactivity ◽  
Cross Coupling ◽  
Underlying Mechanism ◽  
Reductive Elimination ◽  
Coupling Reactions ◽  
Co Catalysts ◽  
Cross Coupling Reactions ◽  
Strain Model

Unstrained cyclic ketones can participate in cooperative Suzuki-Miyaura cross-coupling type reaction using rhodium(I)-based catalyst via C-C bond activation. The regioselectivity indicates a trend where the most substituted side is activated and it is controlled by the beta-substituents. In this work, Density Functional Theory (DFT) calculations have been carried out to disclose the underlying mechanism in the reaction of a ketone series and arylboronate using ylidene as ancillary ligand and pyridine as co-catalysts. The computed energies suggest the reductive elimination step with the highest energy while the reductive elimination has the highest energy barrier. By the means of the Activation Strain Model (ASM) of chemical reactivity, it is found that the ketone strain energy released on the oxidative addition does not control the relativity of the OA reactivity, but indeed is the interaction energy between Rh(I) and C-C bond the ruling effect. The effect of the beta-substituents on regioselectivity has been additionally studied.

scholarly journals Differences between the elimination of early and late transition metals: DFT mechanistic insights into the titanium-catalyzed synthesis of pyrroles from alkynes and diazenes

2017 ◽  
Vol 8 (3) ◽  
pp. 2413-2425 ◽  
Author(s):  
Jiandong Guo ◽  
Xi Deng ◽  
Chunyu Song ◽  
Yu Lu ◽  
Shuanglin Qu ◽  
...  
Keyword(s):  
Transition Metals ◽  
Bond Formation ◽  
Reductive Elimination ◽  
Dft Study ◽  
Late Transition Metals ◽  
Late Transition ◽  
Elimination Pathway ◽  
Back Donation

A DFT study demonstrates that titanium is capable of promoting C–N bond formation via an unconventional reductive elimination pathway featuring back-donation (REBD).

scholarly journals Dramatic mechanistic switch in Sn/AuI group exchanges: transmetalation vs. oxidative addition

2016 ◽  
Vol 52 (23) ◽  
pp. 4305-4308 ◽  
Author(s):  
D. Carrasco ◽  
M. García-Melchor ◽  
J. A. Casares ◽  
P. Espinet
Keyword(s):  
Oxidative Addition ◽  
Reductive Elimination ◽  
Concerted Mechanism ◽  
Elimination Pathway

The mechanism of Ph/X exchange in reactions involving SnPhnBu3 and [AuXL] complexes switches dramatically from the usual concerted mechanism involving Ar/X mixed bridges when X = Cl, to an unexpected oxidative addition/reductive elimination pathway via an AuIII intermediate when X = vinyl.

scholarly journals Cu(OTf)2-Mediated Ionizing Cross-Coupling of N(sp) and N(sp2) with Arylboronic Acids

2020 ◽  
Author(s):  
Allan Watson ◽  
Nicola Bell ◽  
Chao Xu ◽  
James Fyfe ◽  
Julien Vantourout ◽  
...  
Keyword(s):  
Late Stage ◽  
Cross Coupling ◽  
Reductive Elimination ◽  
Subsequent Generation ◽  
Mechanistic Studies ◽  
Arylboronic Acids ◽  
Bond Forming ◽  
Drug Synthesis ◽  
C And N ◽  
Metal Catalyzed

Metal-catalyzed C–N cross-coupling generally forms C–N bonds by reductive elimination from metal complexes bearing covalent C- and N-ligands. We have identified a Cu-mediated C–N cross-coupling that uses a dative N-ligand in the bond forming event, which, in contrast to conventional methods, generates reactive cationic products. Mechanistic studies suggest the process operates via transmetalation of an aryl organoboron to a Cu(II) complex bearing neutral N-ligands, such as nitriles or N-heterocycles. Subsequent generation of a putative Cu(III) complex enables the oxidative C–N coupling to take place, delivering nitrilium intermediates and pyridinium products. The reaction is general for a range of N(sp) and N(sp<sup>2</sup>) precursors and can be applied to drug synthesis and late-stage N-arylation, and the limitations in the methodology are mechanistically evidenced.

scholarly journals Tandem Ullmann–Goldberg Cross-Coupling/Cyclopalladation-Reductive Elimination Reactions and Related Sequences Leading to Polyfunctionalized Benzofurans, Indoles, and Phthalanes

2019 ◽  
Vol 21 (16) ◽  
pp. 6342-6346 ◽  
Author(s):  
Faiyaz Khan ◽  
Mehvish Fatima ◽  
Moheb Shirzaei ◽  
Yen Vo ◽  
Madushani Amarasiri ◽  
...  
Keyword(s):  
Cross Coupling ◽  
Reductive Elimination ◽  
Elimination Reactions
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