Theoretical study of Pd(0)-catalyzed carbohalogenation of alkenes: mechanism and origins of reactivities and selectivities in alkyl halide reductive elimination from Pd(ii) species

2012 ◽  
Vol 3 (6) ◽  
pp. 1987 ◽  
Author(s):  
Yu Lan ◽  
Peng Liu ◽  
Stephen G. Newman ◽  
Mark Lautens ◽  
K. N. Houk
Keyword(s):  
Theoretical Study ◽  
Alkyl Halide ◽  
Reductive Elimination

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.

Transfer of Aryl Halide to Alkyl Halide: Reductive Elimination of Alkylhalide from Alkylpalladium Halides Containingsyn-β-Hydrogen Atoms

2014 ◽  
Vol 53 (52) ◽  
pp. 14533-14537 ◽  
Author(s):  
Wei Hao ◽  
Junnian Wei ◽  
Weizhi Geng ◽  
Wen-Xiong Zhang ◽  
Zhenfeng Xi
Keyword(s):  
Aryl Halide ◽  
Alkyl Halide ◽  
Reductive Elimination ◽  
Hydrogen Atoms

Transfer of Aryl Halide to Alkyl Halide: Reductive Elimination of Alkylhalide from Alkylpalladium Halides Containingsyn-β-Hydrogen Atoms

2014 ◽  
Vol 126 (52) ◽  
pp. 14761-14765 ◽  
Author(s):  
Wei Hao ◽  
Junnian Wei ◽  
Weizhi Geng ◽  
Wen-Xiong Zhang ◽  
Zhenfeng Xi
Keyword(s):  
Aryl Halide ◽  
Alkyl Halide ◽  
Reductive Elimination ◽  
Hydrogen Atoms

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

2019 ◽  
Vol 48 (45) ◽  
pp. 17052-17062 ◽  
Author(s):  
Alexander V. Astakhov ◽  
Safarmurod B. Soliev ◽  
Evgeniy G. Gordeev ◽  
Victor M. Chernyshev ◽  
Valentine P. Ananikov
Keyword(s):  
Dft Calculations ◽  
Relative Stability ◽  
Theoretical Study ◽  
Reductive Elimination ◽  
Catalyst Stability ◽  
Relative Stabilities ◽  
Elimination Reactions ◽  
Catalytic Cycles

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.

scholarly journals 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 ◽  
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.

Sign in / Sign up

Export Citation Format

Share Document