Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States.
J Am Chem Soc. 2022 Nov 30;144(47):21443-21447. doi: 10.1021/jacs.2c10200. Epub 2022 Nov 15.
Hydride transfer catalysis is shown to be enabled by the nonspectator reactivity of a transition metal-bound low-symmetry tricoordinate phosphorus ligand. Complex ·[Ru], comprising a nontrigonal phosphorus chelate (, P(N(-N(2-pyridyl)CH)) and an inert metal fragment ([Ru] = (MeC)Ru), reacts with NaBH to give a metallohydridophosphorane (·[Ru]) by P-H bond formation. Complex ·[Ru] is revealed to be a potent hydride donor (Δ° < 41 kcal/mol, Δ° = 38 ± 2 kcal/mol in MeCN). Taken together, the reactivity of the ·[Ru]/·[Ru] pair comprises a catalytic couple, enabling catalytic hydrodechlorination in which phosphorus is the sole reactive site of hydride transfer.
氢化物转移催化是通过过渡金属配位的低对称三配位磷配体的非旁观反应性来实现的。配合物·[Ru]，包含一个非三角磷螯合物（，P(N(-N(2-吡啶基)CH))和一个惰性金属片段([Ru] = (MeC)Ru)，与 NaBH 反应，通过 P-H 键形成金属氢膦烷（·[Ru]）。配合物·[Ru]被证明是一种有效的氢化物供体（Δ° < 41 kcal/mol，在 MeCN 中为 Δ° = 38 ± 2 kcal/mol）。综上所述，·[Ru]/·[Ru]对的反应性构成了一个催化偶联物，能够实现催化氢脱氯反应，其中磷是氢化物转移的唯一活性位点。
