Pursuing the excision of carbon-centred hexanuclear scandium clusters {CSc

Abstract

A multi-gram synthetic route to black solid {CSc6}I12Sc (1) was developed which comprises the reaction of scandium triiodide, ScI3, with graphite and scandium metal at 850°C. Compound 1 dissolved in N,N-dimethylacetamide (DMA) to form a red solution. Results derived from 45Sc NMR and EPR spectroscopy indicated that a scandium cluster species exists in this solution along with a complex cation [Sc(DMA)6]3+. From these solutions crystals of [Sc(DMA)6]I3 (2) and a red oily product was isolated. Compound 2 was also prepared independently by dissolving ScI3 in DMA and two polymorphs, orthorhombic 2O and monoclinic 2M were crystallised. {CSc6}I12Sc (1) also dissolved in THF yielding a red solution which contains [ScI6]3− and a scandium cluster species, as analysed by 45Sc NMR and EPR spectroscopy.