25117-68-4Relevant academic research and scientific papers
Detection and characterization of mononuclear Pd(I) complexes supported by N2S2 and N4 tetradentate ligands
Luo, Jia,Mirica, Liviu M.,Rath, Nigam P.,Tran, Giang N.
supporting information, p. 15659 - 15669 (2020/11/20)
Palladium is a versatile transition metal used to catalyze a large number of chemical transformations, largely due to its ability to access various oxidation states (0, I, II, III, and IV). Among these oxidation states, Pd(I) is arguably the least studied, and while dinuclear Pd(I) complexes are more common, mononuclear Pd(I) species are very rare. Reported herein are spectroscopic studies of a series of Pd(I) intermediates generated by the chemical reduction at low temperatures of Pd(II) precursors supported by the tetradentate ligands 2,11-dithia[3.3](2,6)pyridinophane (N2S2) and N,N′-di-tert-butyl-2,11-diaza[3.3](2,6)pyridinophane (tBuN4): [(N2S2)PdII(MeCN)]2(OTf)4 (1), [(N2S2)-PdIIMe]2(OTf)2 (2), [(N2S2)PdIICl](OTf) (3), [(N2S2)PdIIX](OTf)2 (X = tBuNC 4, PPh3 5), [(N2S2)PdIIMe(PPh3)](OTf) (6), and [(tBuN4)PdIIX2](OTf)2 (X = MeCN 8, tBuNC 9). In addition, a stable Pd(I) dinuclear species, [(N2S2)PdI(μtBuNC)]2(ClO4)2 (7), was isolated upon the electrochemical reduction of 4 and structurally characterized. Moreover, the (tBuN4)PdI intermediates, formed from the chemical reduction of [(tBuN4)PdIIX2](OTf)2 (X = MeCN 8, tBuNC 9) complexes, were investigated by EPR spectroscopy, X-ray absorption spectroscopy (XAS), and DFT calculations and compared with the analogous (N2S2)PdI systems. Upon probing the stability of Pd(I) species under different ligand environments, it is apparent that the presence of soft ligands such as tBuNC and PPh3 significantly improves the stability of Pd(I) species, which should make the isolation of mononuclear Pd(I) species possible.
Oxidative reactivity of (N2S2)PdRX complexes (R = Me, Cl; X = Me, Cl, Br): Involvement of palladium(III) and palladium(IV) intermediates
Luo, Jia,Rath, Nigam P.,Mirica, Liviu M.
supporting information, p. 3343 - 3353 (2013/07/19)
A series of (N2S2)PdRX complexes (N2S2 = 2,11-dithia[3.3](2,6) pyridinophane; R = X = Me, 1; R = Me, X = Cl, 2; R = Me, X = Br, 3; R = X = Cl, 4) were synthesized, and their structural and electronic properties were investigated. X-ray crystal structures
