Intramolecular Redox-Active Ligand-to-Substrate Single-Electron Transfer: Radical Reactivity with a Palladium(II) Complex
摘要:
Coordination of the redox-active tridentate NNO ligand L-H2 to Pd-II yields the paramagnetic iminobenzosemiquinonato complex 3. Single-electron reduction of 3 yields diamagnetic amidophenolato complex 4, capable of activating aliphatic azide 5. Experimental and computational studies suggest a redox-noninnocent pathway wherein the redox-active ligand facilitates intramolecular ligand-to-substrate single-electron transfer to generate an open-shell singlet "nitrene-substrate radical, ligand radical", enabling subsequent radical-type C-H amination reactivity with Pd-II.
Redox-Active-Ligand-Mediated Formation of an Acyclic Trinuclear Ruthenium Complex with Bridging Nitrido Ligands
作者:Bidraha Bagh、Daniël L. J. Broere、Maxime A. Siegler、Jarl Ivar van der Vlugt
DOI:10.1002/anie.201603659
日期:2016.7.11
aminophenol ligand to RuII followed by aerobic oxidation generates two diamagnetic RuIII species [1 a (cis) and 1 b (trans)] with ligand‐centered radicals. The reaction of 1 a/1 b with excess NaN3 under inert atmosphere resulted in the formation of a rare bis(nitrido)‐bridged trinuclear ruthenium complex with two nonlinear asymmetrical Ru‐N‐Ru fragments. The spontaneous reduction of the ligand centered
Selective Manipulation of Well‐Defined Trinuclear Pd(II)‐Complexes
作者:Siuli Das、Julia Buschermöhle、Dirk W. Zant、M. Schmidtmann、Jarl Ivar van der Vlugt
DOI:10.1002/chem.202400044
日期:2024.4.11
Several strategies are available to design well‐defined multimetallic molecular entities bearing functional ligands. Substoichiometric exchange reactions in the coordination sphere of pre‐existing multinuclear precursors are relatively underexploited in this context. Palladium(II) acetate is not a mononuclear compound in the solid state but rather exists as a trimer, i. e. [Pd3(OAc)6]. Although this material is ubiquitously used to synthesize mononuclear Pd species, it may principally also lend itself to selective exchange of some of the edge‐sharing acetate units in its triangular motif, whilst keeping the overall multinuclear architecture intact. Strikingly, little is known about the controlled manipulation and substoichiometric substitution chemistry of this well‐defined conglomerate. We herein conclusively demonstrate that, for the first time, the targeted exchange of two or four acetate units from the Pd3(acetate)6 platform is possible, thereby installing either one or two new tridentate ligands onto this trinuclear architecture. Follow‐up exchange and substitution chemistry is available without disrupting the multimetallic nature of the core structure. New complexes 2–7 are all conclusively characterized using multinuclear NMR spectroscopy, UV‐vis and IR spectroscopy as well as X‐ray diffraction analysis.