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

2016 ◽  
Vol 94 (12) ◽  
pp. 1028-1037 ◽  
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.

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

2019 ◽  
Vol 9 (3) ◽  
pp. 646-651 ◽  
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.

A theoretical study of weak interactions in phenylenediamine homodimer clusters

2016 ◽  
Vol 18 (42) ◽  
pp. 29249-29257 ◽  
Author(s):  
Chengqian Yuan ◽  
Haiming Wu ◽  
Meiye Jia ◽  
Peifeng Su ◽  
Zhixun Luo ◽  
...  
Keyword(s):  
Density Functional Theory ◽  
Dft Calculations ◽  
Intermolecular Interactions ◽  
Density Functional ◽  
Theoretical Study ◽  
Natural Bond Orbital ◽  
Weak Interactions ◽  
Interaction Energies ◽  
Functional Theory ◽  
Weak Intermolecular Interactions

Utilizing dispersion-corrected density functional theory (DFT) calculations, we demonstrate the weak intermolecular interactions of phenylenediamine dimer (pdd) clusters, emphasizing the local lowest energy structures and decomposition of interaction energies by natural bond orbital (NBO) and atoms in molecule (AIM) analyses.

Structure-activity relationships in the production of olefins from alcohols and ethers: a first-principles theoretical study

2015 ◽  
Vol 5 (9) ◽  
pp. 4547-4555 ◽  
Author(s):  
Pavlo Kostetskyy ◽  
Giannis Mpourmpakis
Keyword(s):  
Density Functional Theory ◽  
Dft Calculations ◽  
Lewis Acid ◽  
First Principles ◽  
Density Functional ◽  
Theoretical Study ◽  
Functional Theory ◽  
Structure Activity Relationships ◽  
Structure Activity

Olefin formation pathways on Lewis acid (LA) sites of Al2O3, Ga2O3 and In2O3 and gallium- and indium-doped alumina were investigated using Density Functional Theory (DFT) calculations.

scholarly journals Distribution of dopant ions around poly(3,4-ethylenedioxythiophene) chains: a theoretical study

2017 ◽  
Vol 19 (15) ◽  
pp. 9889-9899 ◽  
Author(s):  
Jordi Casanovas ◽  
David Zanuy ◽  
Carlos Alemán
Keyword(s):  
Density Functional Theory ◽  
Boundary Conditions ◽  
Dft Calculations ◽  
Density Functional ◽  
Periodic Boundary ◽  
Theoretical Study ◽  
Periodic Boundary Conditions ◽  
Polymer Chains ◽  
Functional Theory

The effect of counterions and multiple polymer chains on the properties and structure of poly(3,4-ethylenedioxythiophene) (PEDOT) doped with ClO4− has been examined using density functional theory (DFT) calculations with periodic boundary conditions (PBCs).

Mechanistic insight into H2-mediated Ni surface diffusion and deposition to form branched Ni nanocrystals: a theoretical study

2020 ◽  
Vol 22 (41) ◽  
pp. 23869-23877
Author(s):  
Yan Li ◽  
Ning Liu ◽  
Chengna Dai ◽  
Ruinian Xu ◽  
Bin Wu ◽  
...  
Keyword(s):  
Density Functional Theory ◽  
Dft Calculations ◽  
Ab Initio ◽  
Surface Diffusion ◽  
Density Functional ◽  
Theoretical Study ◽  
Functional Theory ◽  
Mechanistic Insight ◽  
Insight Into

Present work investigates the kinetic role of H2 during Ni surface diffusion and deposition to generate branched Ni nanostructures by employing density functional theory (DFT) calculations and ab initio molecule dynamic (AIMD) simulations.

Theoretical study on nanostructural modifications of the Si(111) surface

2019 ◽  
Vol 18 (01) ◽  
pp. 1950005
Author(s):  
Yue-Hang Dong ◽  
Xiao-Hui Liu ◽  
Wan-Sheng Su ◽  
Li-Zhen Zhao ◽  
Qing-Jun Zang ◽  
...  
Keyword(s):  
Density Functional Theory ◽  
Optical Properties ◽  
Optical Absorption ◽  
Dft Calculations ◽  
Electronic Structures ◽  
Density Functional ◽  
Theoretical Study ◽  
Surface Modifications ◽  
Thermal Stabilities ◽  
Functional Theory

Modified Si(111) surface with designed nanostructural modifications including grown pits, nanobars and nanoislands as well as deposited hill-, diamond- and cage-like nanoclusters were studied using density-functional theory (DFT) calculations. The thermal stabilities, electronic structures and optical properties of these various nanostructural modifications of the Si(111) surface were calculated and discussed. The results indicate that the optical absorption of the modified Si(111) surface can be enhanced by these surface modifications especially when depositing diamond-like nanoclusters on the surface.

Dissociative adsorption of a multifunctional compound on a semiconductor surface: a theoretical study of the adsorption of hydroxylamine on Ge(100)

2018 ◽  
Vol 20 (22) ◽  
pp. 15335-15343 ◽  
Author(s):  
Hyunkyung Park ◽  
Do Hwan Kim
Keyword(s):  
Density Functional Theory ◽  
Dft Calculations ◽  
Density Functional ◽  
Theoretical Study ◽  
Dissociative Adsorption ◽  
Adsorption Behavior ◽  
Semiconductor Surface ◽  
Functional Theory

The adsorption behavior of hydroxylamine on a Ge(100) surface was investigated using density functional theory (DFT) calculations.

scholarly journals Incorporation of Iron(II) and (III) in Hydroxyapatite—A Theoretical Study

Crystals ◽  
2021 ◽  
Vol 11 (10) ◽  
pp. 1219
Author(s):  
Olga Nikolaevna Makshakova ◽  
Daria Vladimirovna Shurtakova ◽  
Alexey Vladimirovich Vakhin ◽  
Peter Olegovich Grishin ◽  
Marat Revgerovich Gafurov
Keyword(s):  
Crystal Structure ◽  
Density Functional Theory ◽  
Dft Calculations ◽  
Potential Application ◽  
Density Functional ◽  
Theoretical Study ◽  
Charge Compensation ◽  
Comprehensive Analysis ◽  
Functional Theory ◽  
Experimental Works

Hydroxyapatite (Ca10(PO4)6(OH)2, HAp) doped with various transition metals has generated great interest in view of its potential application in a wide variety of fields, including in catalysis as a support with a series of attractive properties. Despite a large number of experimental works devoted to the synthesis and application of iron-substituted hydroxyapatites, problems concerning the location, introduced defects, and charge compensation schemes for Fe2+ and/or Fe3+ cations in the crystal structure of HAp remain unclear. This paper is devoted to the comprehensive analysis of iron (II) and (III) introduction into the HAp lattice by density functional theory (DFT) calculations. We show that the inclusion of Fe2+ in the Ca(1) and Ca(2) positions of HAp is energetically comparable. For the Fe3+, there is a clear preference to be included in the Ca(2) position. The inclusion of iron results in cell contraction, which is more pronounced in the case of Fe3+. In addition, Fe3+ may form a shorter linkage to oxygen atoms. The incorporation of both Fe2+ and Fe3+ leads to notable local reorganization in the HAp cell.

A theoretical study on the oxidation of alkenes to aldehydes catalyzed by ruthenium porphyrins using O2 as the sole oxidant

2018 ◽  
Vol 47 (15) ◽  
pp. 5286-5297 ◽  
Author(s):  
Lin-Lin Zhang ◽  
Xiang-Yun Wang ◽  
Kun-Yao Jiang ◽  
Bing-Yuan Zhao ◽  
Hui-Min Yan ◽  
...  
Keyword(s):  
Density Functional Theory ◽  
Dft Calculations ◽  
Density Functional ◽  
Theoretical Study ◽  
Functional Theory ◽  
Ruthenium Porphyrin ◽  
Catalyzed Oxidation

Density functional theory (DFT) calculations were used to study the ruthenium porphyrin-catalyzed oxidation of styrene to generate an aldehyde.

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

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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