Room-temperature oxidation of thulium-metal nanoparticles to the thulium oxocluster [Tm${}_5$O(O${}^i$Pr)${}_{13}$]

Zerovalent thulium nanoparticles (2.2±0.3 nm in size) are used as the starting material to prepare single crystals of the thulium oxocluster [Tm${}_5$O(O${}^i$Pr)${}_{13}$]. The reaction is performed by controlled oxidation of the Tm(0) nanoparticles at room temperature (25°C) in isopropanol. The pentanuclear oxocluster contains a non-charged molecular unit with a central Tm${}_5$O core and five µ${}_1$-, four µ${}_2$-, and four µ${}_3$-bridging (O${}^i$Pr)${}^{-}$ ligands. Single-crystal structure analysis (P2${}_1$/n , a=1247.7(6), b=2146.2(15), c=2056.6(9) pm, β=93.23(1)°) and infrared spectroscopy confirm the oxidation of HO${}^i$Pr with formation of H${}_2$ and (O${}^i$Pr)${}^{-}$. Temperature-dependent measurements show antiferromagnetic coupling. Such a polynuclear [Ln${}_5$O(O${}^i$Pr)${}_{13}$] oxocluster (Ln: lanthanide) is prepared with thulium-metal nanoparticles as a starting material for the first time and points to the suitability of reactive rare-earth metal nanoparticles as starting materials. (© 2022 The Authors. Zeitschrift für anorganische und allgemeine Chemie published by Wiley-VCH GmbH)