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Mechanistic Features in Al(I)-Mediated Oxidative Addition of Aryl C-F Bonds: Insights From Density Functional Theory Calculations.

ABSTRACT: The oxidative addition of a range of robust aryl C-F bonds to a single Al(I) center supported by a (NacNac)- bidentate ligand ((NacNac)- = [ArNC(Me)CHC(Me)NAr]- and Ar = 2,6- Pr2i C6H3) have been explored by density functional theory calculations. Our calculations demonstrate that the Al(I) center-mediated C-F insertion generally proceeds via the concerted mechanism that involve both the donation ( nAl→σC-F* ) and back-donation ( σF(p)→πAl(p)* ) interactions. In addition, the predicted free energy barriers for the C-F bond activation show good agreement with the experimental information available. Finally, the comparative studies show that B(I) is the most active among group III metals (B, Al, Ga), thus supplying a testable prediction for experiments.

SUBMITTER: Zhang X

PROVIDER: S-EPMC6733912 | biostudies-literature | 2019

REPOSITORIES: biostudies-literature

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Mechanistic Features in Al(I)-Mediated Oxidative Addition of Aryl C-F Bonds: Insights From Density Functional Theory Calculations.

Zhang Xiangfei X Li Ping P Wang Binju B Cao Zexing Z

Frontiers in chemistry 20190903

The oxidative addition of a range of robust aryl C-F bonds to a single Al(I) center supported by a (NacNac)- bidentate ligand ((NacNac)- = [ArNC(Me)CHC(Me)NAr]- and Ar = 2,6- Pr 2 i C6H3) have been explored by density functional theory calculations. Our calculations demonstrate that the Al(I) center-mediated C-F insertion generally proceeds via the concerted mechanism that involve both the donation ( n Al → σ C - F * ) and back ...[more]

PMID: 31552218

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