摘要
Carbon dioxide is expected to be employed as an inexpensive and potential feedstock of C 1 sources for the mass production of valuable chemicals and fuel. Versatile chemical transformations of CO 2 , i.e. insertion of CO 2 producing bicarbonate/acetate/formate, cleavage of CO 2 yielding μ-CO/μ-oxo transition-metal complexes, and electrocatalytic reduction of CO 2 affording CO/HCOOH/CH 3 OH/CH 4 /C 2 H 4 /oxalate were well documented. Herein, we report a novel pathway for the reductive activation of CO 2 by the [Ni III (OMe)(P(C 6 H 3 -3-SiMe 3 -2-S) 3 )] - complex, yielding the [Ni III (κ 1 -OCO - )(P(C 6 H 3 -3-SiMe 3 -2-S) 3 )] - complex. The formation of this unusual Ni III (κ 1 -OCO - ) complex was characterized by single-crystal X-ray diffraction, EPR, IR, SQUID, Ni/S K-edge X-ray absorption spectroscopy, and Ni valence-To-core X-ray emission spectroscopy. The inertness of the analogous complexes [Ni III (SPh)], [Ni II (CO)], and [Ni II (N 2 H 4 )] toward CO 2 , in contrast, demonstrates that the ionic [Ni III (OMe)] core attracts the binding of weak σ-donor CO 2 and triggers the subsequent reduction of CO 2 by the nucleophilic [OMe] - in the immediate vicinity. This metal-ligand cooperative activation of CO 2 may open a novel pathway promoting the subsequent incorporation of CO 2 in the buildup of functionalized products.