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Catalytic Hydrodefluorination via Oxidative Addition, Ligand Metathesis, and Reductive Elimination at Bi(I)/Bi(III) Centers.

ABSTRACT: Herein, we report a hydrodefluorination reaction of polyfluoroarenes catalyzed by bismuthinidenes, Phebox-Bi(I) and OMe-Phebox-Bi(I). Mechanistic studies on the elementary steps support a Bi(I)/Bi(III) redox cycle that comprises C(sp²)-F oxidative addition, F/H ligand metathesis, and C(sp²)-H reductive elimination. Isolation and characterization of a cationic Phebox-Bi(III)(4-tetrafluoropyridyl) triflate manifests the feasible oxidative addition of Phebox-Bi(I) into the C(sp²)-F bond. Spectroscopic evidence was provided for the formation of a transient Phebox-Bi(III)(4-tetrafluoropyridyl) hydride during catalysis, which decomposes at low temperature to afford the corresponding C(sp²)-H bond while regenerating the propagating Phebox-Bi(I). This protocol represents a distinct catalytic example where a main-group center performs three elementary organometallic steps in a low-valent redox manifold.

SUBMITTER: Pang Y

PROVIDER: S-EPMC8377712 | biostudies-literature |

REPOSITORIES: biostudies-literature

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Bimetallic reductive elimination from dinuclear Pd(III) complexes.

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Lewis acid-assisted Ir(iii) reductive elimination enables construction of seven-membered-ring sulfoxides.

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