Arene C–H bond activation and methane formation by a methylplatinum(ii) complex: experimental and theoretical elucidation of the mechanism

2019 ◽  
Vol 43 (21) ◽  
pp. 8005-8014 ◽  
Author(s):  
Asma Nahaei ◽  
S. Masoud Nabavizadeh ◽  
Fatemeh Niroomand Hosseini ◽  
S. Jafar Hoseini ◽  
Mahdi M. Abu-Omar
Keyword(s):  
Bond Activation ◽  
Oxidative Addition ◽  
Methane Formation ◽  
Donor Atom ◽  
Computational Investigation ◽  
Hydride Complex

A combined experimental/computational investigation reveals that the cyclometalation of [PtMe2(DMSO)2], 1, by HC^N ligands proceeds via HC^N coordination through the N donor atom, oxidative addition of the arene C–H bond, and final dissociation of methane from a platinum hydride complex.

An N-Heterocyclic Carbene/Iridium Hydride Complex from the Oxidative Addition of a Ferrocenyl-Bisimidazolium Salt: Implications for Synthesis

2004 ◽  
Vol 44 (3) ◽  
pp. 444-447 ◽  
Author(s):  
Mónica Viciano ◽  
Elena Mas-Marzá ◽  
Macarena Poyatos ◽  
Mercedes Sanaú ◽  
Robert H. Crabtree ◽  
...  
Keyword(s):  
Oxidative Addition ◽  
Hydride Complex

scholarly journals Palladium-Catalysed C–F Alumination of Fluorobenzenes: Mechanistic Diversity and Origin of Selectivity

2020 ◽  
Author(s):  
Feriel Rekhroukh ◽  
Wenyi Chen ◽  
Ryan Brown ◽  
Andrew J. P. White ◽  
Mark Crimmin
Keyword(s):  
Dft Calculations ◽  
Bond Activation ◽  
Oxidative Addition ◽  
Fluorine Content ◽  
Model Potential ◽  
Heterometallic Complex ◽  
Experimental Support ◽  
Highly Active ◽  
Reaction Proceeds ◽  
Directing Group

A palladium pre-catalyst, [Pd(PCy<sub>3</sub>)<sub>2</sub>] is reported for the efficient and selective C–F alumination of fluorobenzenes with the aluminium(I) reagent [{(ArNCMe)<sub>2</sub>CH}Al] (<b>1</b>, Ar = 2,6-di-iso-propylphenyl). The catalytic protocol results in the transformation of sp<sup>2</sup> C–F bonds to sp<sup>2</sup> C–Al bonds and provides a route into reactive organoaluminium complexes (<b>2a-h</b>) from fluorocarbons. The catalyst is highly active. Reactions proceed within 5 minutes at 25 ºC (and at appreciable rates at even –50 ºC) and the scope includes low-fluorine-content substrates such as fluorobenzene, difluorobenzenes and trifluorobenzenes. The reaction proceeds with complete chemoselectivity (C–F vs C–H) and high regioselectivities ( >90% for C–F bonds adjacent to the most acidic C–H sites). The heterometallic complex [Pd(PCy<sub>3</sub>)(<b>1</b>)<sub>2</sub>] was shown to be catalytically competent. Catalytic C–F alumination proceeds with a KIE of 1.1–1.3. DFT calculations have been used to model potential mechanisms for C–F bond activation. These calculations suggest that two competing mechanisms may be in operation. Pathway 1 involves a ligand-assisted oxidative addition to [Pd(<b>1</b>)<sub>2</sub>] and leads directly to the product. Pathway 2 involves a stepwise C–H to C–F functionalisation mechanism in which the C–H bond is broken and reformed along the reaction coordinate, allowing it to act as a directing group for the adjacent C–F site. This second mechanism explains the experimentally observed regioselectivity. Experimental support for this C–H activation playing a key role in C–F alumination was obtained by employing [{(MesNCMe)<sub>2</sub>CH}AlH<sub>2</sub>] (<b>3</b>, Mes = 2,4,6-trimethylphenyl) as a reagent in place of 1. In this instance, the kinetic C–H alumination intermediate could be isolated. Under catalytic conditions this intermediate converts to the thermodynamic C–F alumination product.

scholarly journals Si–C(sp3) bond activation through oxidative addition at a Rh(i) centre

2020 ◽  
Vol 49 (17) ◽  
pp. 5416-5419
Author(s):  
S. Azpeitia ◽  
A. J. Martínez-Martínez ◽  
M. A. Garralda ◽  
A. S. Weller ◽  
M. A. Huertos
Keyword(s):  
Room Temperature ◽  
Bond Activation ◽  
Oxidative Addition

Rhodium promoted a fast, quantitative and room temperature Si–CH3 bond activation.

Hydrolysis of the aluminum hydride complex of permethylcylopentadienyltitanocene with C-H bond activation

1986 ◽  
Vol 35 (4) ◽  
pp. 874-875
Author(s):  
�. B. Lobkovskii ◽  
A. I. Sizov ◽  
B. M. Bulychev ◽  
G. L. Soloveichik ◽  
I. V. Sokolova
Keyword(s):  
Bond Activation ◽  
Aluminum Hydride ◽  
Hydride Complex ◽  
Hydrolysis Of

An N-Heterocyclic Carbene/Iridium Hydride Complex from the Oxidative Addition of a Ferrocenyl-Bisimidazolium Salt: Implications for Synthesis

2004 ◽  
Vol 117 (3) ◽  
pp. 448-451 ◽  
Author(s):  
Mónica Viciano ◽  
Elena Mas-Marzá ◽  
Macarena Poyatos ◽  
Mercedes Sanaú ◽  
Robert H. Crabtree ◽  
...  
Keyword(s):  
Oxidative Addition ◽  
Hydride Complex

What drives the H-abstraction reaction in bio-mimetic oxoiron-bTAML complexes? A computational investigation

2018 ◽  
Vol 20 (20) ◽  
pp. 13845-13850
Author(s):  
Anagh Mukherjee ◽  
Santanu Pattanayak ◽  
Sayam Sen Gupta ◽  
Kumar Vanka
Keyword(s):  
Bond Activation ◽  
Computational Investigation ◽  
Abstraction Reaction

Monomeric iron-oxo units have been confirmed as intermediates involved in the C–H bond activation in various metallo-enzymes.

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