Structural characterization of a lanthanum bistriflimide complex, La(N(SO2CF3)2)3(H2O)3, and an investigation of La, Sm, and Eu electrochemistry in a room-temperature ionic liquid, [Me3NnBu][N(SO2CF3)2]

The reduction of selected lanthanide cations to the zerovalent state in the room-temperature ionic liquid [(Me3NBu)-Bu-n][TFSI] is reported (where TFSI = bistriflimide, [N(SO2CF3)(2)](-)). The lanthanide cations were introduced to the melt as the TFSl hydrate complexes [Ln(TFSI)(3)(H2O)(3)] (where Ln = La-III, Sm-II or Eu-III). The lanthanum compound [La(TFSl)(3)(H2O)(3)] has been crystallographically characterized, revealing the first structurally characterized f-element TFSl complex. The lanthanide in all three complexes was shown to be reducible to the metallic state in [(Me3NBu)-Bu-n][TFSI]. For both the Eu and Sm complexes, reduction to the metallic state was achieved via divalent species, and there was an additional observation of the electrodeposition of Eu metal.