Simple Preparations of the Anhydrous and Solvent-Free Uranyl and Cerium(IV) Triflates UO2(OTf)2 and Ce(OTf)4 − Crystal Structures of UO2(OTf)2(py)3 and [{UO2(py)4}2(μ-O)][OTf]2

Treatment of UO3 with pure triflic acid TfOH at 110 °C or with boiling triflic anhydride TfOTf afforded [UO2(OTf)2] (1) in high yields. The latter was also prepared by the reaction of UO3 with TfOH in water, or by dehydration of [UO2(OTf)2(H2O)n] in boiling TfOTf. Anhydrous [Ce(OTf)4] (2) was similarly obtained from the commercially hydrated compound. X-ray analysis revealed that in [UO2(OTf)2(py)3] (3), the triflate ligands are monodentate whereas they are dissociated in [{UO2(py)4}2(μ-O)][OTf]2 (4).