Relative stabilities of M/NHC complexes (M = Ni, Pd, Pt) against R–NHC, X–NHC and X–X couplings in M(0)/M(ii) and M(ii)/M(iv) catalytic cycles: a theoretical study

DFT calculations reveal relative stability of MII/NHC and MIV/NHC complexes of nickel, palladium and platinum against the R–NHC coupling and various reductive elimination reactions that influence catalyst stability/decomposition.

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Theoretical study on the mechanism of iridium-catalyzed γ-functionalization of primary alkyl C–H bonds

Canadian Journal of Chemistry ◽

10.1139/cjc-2016-0287 ◽

2016 ◽

Vol 94 (12) ◽

pp. 1028-1037 ◽

Cited By ~ 4

Author(s):

Zhe Li ◽

Miaoren Xia ◽

Russell J. Boyd

Keyword(s):

Density Functional Theory ◽

Dft Calculations ◽

Experimental Observation ◽

Density Functional ◽

Theoretical Study ◽

Reductive Elimination ◽

Catalytic Cycle ◽

Catalyst Precursor ◽

Functional Theory ◽

Initial Formation

The mechanism of the iridium-catalyzed functionalization of a primary C–H bond at the γ position of an alcohol 5 is investigated by density functional theory (DFT) calculations. A new IrIII–IrV mechanism is found to be more feasible than the previously reported IrI–IrIII mechanism. 10 In the IrIII–IrV mechanism, the reaction begins with the initial formation of (Me4phen)IrIII(H)[Si(OR)Et2]2 from the catalyst precursor, [Ir(cod)OMe]2 (cod = 1,5-cyclooctadiene). The catalytic cycle includes five steps: (1) the insertion of norbornene into the Ir–H bond to produce (Me4phen)IrIII(norbornyl)[Si(OR)Et2]2 (R = –CH(C2H5)C3H7); (2) the Si–H oxidative addition of HSi(OR)Et2 to form (Me4phen)IrVH(norbornyl)[Si(OR)Et2]3; (3) the reductive elimination of norbornane to furnish (Me4phen)IrIII[Si(OR)Et2]3; (4) the intramolecular C–H activation of the primary C–H bond at the γ position; and (5) the Si–C reductive elimination to produce the final product and regenerate the catalyst. The highest barrier in the IrIII–IrV mechanism is 7.3 kcal/mol lower than that of the IrI–IrIII mechanism. In addition, the regioselectivity of the C–H activation predicted by this new IrIII–IrV mechanism is consistent with experimental observation.

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A Theoretical Study on Pd-catalyzed, Friedel-Crafts Intermolecular Acylation: Does Generated In Situ Aroyl Triflate Act as A Reactive Electrophile to Functionalize C–H Bond of Arenes?

Catalysts ◽

10.3390/catal9020141 ◽

2019 ◽

Vol 9 (2) ◽

pp. 141

Author(s):

Rong Chang ◽

Ye Tian ◽

Niu Li ◽

Jin Bai ◽

Huimin Yan ◽

...

Keyword(s):

Dft Calculations ◽

Theoretical Study ◽

Reductive Elimination ◽

Pd Catalysts ◽

Bond Functionalization ◽

Rate Determining Step ◽

Co Insertion ◽

Experimental Findings ◽

Key Steps

The mechanism of Pd-catalyzed, Friedel-Crafts intermolecular acylation of arenes to ketones was comprehensively investigated by using DFT calculations. The calculated results revealed that this transformation was composed of several key steps: C–I bond oxidative addition, CO insertion, reductive elimination and C–H bond functionalization. Of these steps, the last was found to be the rate–determining step, and it occurred much more easily with strongly electrophilic aroyl triflate compared to other resultant counterparts. In addition, our calculation provides a rationale for experimental findings that simple Pd salts exhibit superior catalytic abilities compared to phosphine-ligated Pd catalysts.

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Probing enantioselectivity in rhodium-catalyzed Si–C bond cleavage to construct silicon-stereocenters: a theoretical study

Catalysis Science & Technology ◽

10.1039/c8cy02261e ◽

2019 ◽

Vol 9 (3) ◽

pp. 646-651 ◽

Cited By ~ 6

Author(s):

Zhaoyuan Yu ◽

Tao Zhang ◽

Ruopeng Bai ◽

Yu Lan

Keyword(s):

Density Functional Theory ◽

Dft Calculations ◽

Density Functional ◽

Theoretical Study ◽

Bond Cleavage ◽

Oxidative Addition ◽

Reductive Elimination ◽

Functional Theory ◽

Elimination Process

Density functional theory (DFT) calculations indicate that favorable oxidative addition/reductive elimination process from arylrhodium complex determines the enantioselectivity.

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Structure and New Substructure of α-Ti2O3: X-ray Diffraction and Theoretical Study

Journal of Modern Materials ◽

10.21467/jmm.8.1.3-11 ◽

2021 ◽

Vol 8 (1) ◽

pp. 3-11

Author(s):

Soumia Merazka ◽

Lamia Hammoudi ◽

Mohammed Kars ◽

Mohamed Sidoumou ◽

Thierry Roisnel

Keyword(s):

Crystal Structure ◽

Density Functional Theory ◽

Dft Calculations ◽

Relative Stability ◽

Density Functional ◽

Theoretical Study ◽

X Ray Diffraction ◽

Functional Theory ◽

X Ray ◽

High Coordination

The Crystal structure of both α-Ti2O3 and its new substructure with a halved c-axis has been investigated by single-crystal X-ray diffraction and density functional theory (DFT) calculations. The α-Ti2O3 substructure described in the R-3m space group, reveals an unusual 12-fold high coordination of Ti atoms forming edge and face-sharing distorted hexagonal prisms TiO12 stacking along the c-axis. The Hubbard-corrections predict a close bandgap for both α-Ti2O3 and its substructure; whereas a comparative study of their relative stability indicates that the substructure is thermodynamically less stable.

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Reversible Oxidative-Addition and Reductive-Elimination of Thiophene from a Titanium Complex and Its Thermally-Induced Hydrodesulfurization Chemistry

10.26434/chemrxiv.10321946.v1 ◽

2019 ◽

Author(s):

Alejandra Gomez-Torres ◽

J. Rolando Aguilar-Calderón ◽

Carlos Saucedo ◽

Aldo Jordan ◽

Alejandro J. Metta-Magaña ◽

...

Keyword(s):

Dft Calculations ◽

Ring Opening ◽

Thiophene Ring ◽

Oxidative Addition ◽

Reductive Elimination ◽

Thermally Induced ◽

Titanium Complex

The masked Ti(II) synthon (Ketguan)(η6-ImDippN)Ti (1) oxidatively adds across thiophene to give ring-opened (Ketguan)(ImDippN)Ti[κ2-S(CH)3CH] (2). Complex 2 is photosensitive, and upon exposure to light, reductively eliminates thiophene to regenerate 1 – a rare example of early-metal mediated oxidative-addition/reductive-elimination chemistry. DFT calculations indicate strong titanium π-backdonation to the thiophene π*-orbitals leads to the observed thiophene ring opening across titanium, while a proposed photoinduced LMCT promotes the reverse thiophene elimination from 2. Finally, pressurizing solutions of 2 with H2 (150 psi) at 80 °C leads to the hydrodesulfurization of thiophene to give the Ti(IV) sulfide (Ketguan)(ImDippN)Ti(S) (3) and butane.

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Theoretical study, NBO analysis, HOMO/LUMO and first static hyperpolarizability for structural prediction of new ligands 1X-tri-R-σ3λ3-phosphacyclohexadienyl anion using DFT calculations

Журнал структурной химии ◽

10.26902/jsc_id52151 ◽

2020 ◽

Vol 61 (2) ◽

Keyword(s):

Dft Calculations ◽

Theoretical Study ◽

Nbo Analysis ◽

Structural Prediction ◽

Homo Lumo

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Force-modulated reductive elimination from platinum(ii) diaryl complexes

Chemical Science ◽

10.1039/d1sc03182a ◽

2021 ◽

Author(s):

Yichen Yu ◽

Chenxu Wang ◽

Liqi Wang ◽

Cai-Li Sun ◽

Roman Boulatov ◽

...

Keyword(s):

Transition State ◽

Reductive Elimination ◽

Mechanical Force ◽

Elimination Reactions

The influence of mechanical force on the rates of model reductive elimination reactions depends on the structure of the force-transducing ligand and provides a measure of geometry changes upon reaching the transition state.

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Photoelectron Spectroscopy and Theoretical Study of AlnC5-/0 (n = 1-5) clusters: Structural Evolution, Relative Stability of Star-Like Cluster, and Planar Tetracoordinate Carbon Structure

Physical Chemistry Chemical Physics ◽

10.1039/d0cp06081j ◽

2021 ◽

Author(s):

Chao-Jiang Zhang ◽

Peng Wang ◽

Xi-Ling Xu ◽

Hong-Guang Xu ◽

Weijun Zheng

Keyword(s):

Gas Phase ◽

Photoelectron Spectroscopy ◽

Relative Stability ◽

Theoretical Study ◽

Structural Evolution ◽

Carbon Structure ◽

Anion Photoelectron Spectroscopy

The AlnC5- (n = 1-5) clusters were detected in the gas-phase and were investigated by mass-selected anion photoelectron spectroscopy. The structures of AlnC5-/0 (n = 1-5) were explored by theoretical...

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