Cerium masquerading as a Group 4 element: synthesis, structure and computational characterisation of [CeCl{N(SiMe3)2}3]

Abstract

Oxidation of the three-coordinate cerium amide [Ce(N-(SiMe3)2)3] with TeCl4 in toluene solution yields purple, diamagnetic [CeCl(N(SiMe3)2)3], whose structure has been examined by X-ray crystallographic and computational methods.

Controlled Redox Chemistry at Cerium within a Tripodal Nitroxide Ligand Framework

“…Again, the structural metrics were consistent with a central Ce IV cation (Table 2). The CeCl bond length of 2.7436(8) Å was significantly longer than that of 2.597(2) Å found in CeCl[N(SiMe 3 ) 2 ] 3 indicative of the larger steric demand of the TriNO x 3− ligand 17. However, the CeCl bond length in 3‐Cl was significantly shorter than that of 3.0080(3) Å in the known [{Ce(NN′ 3 )} 2 (μ‐Cl)], in which NN′ 3 =[N(CH 2 CH 2 N(SiMe 2 t Bu] 3− , due to the bridging mode of the chloride ligand between the Ce III/IV sites in the latter 6a…”

The First Cationic Complex of Tetravalent Cerium

“…With 2.437(3) and 2.423(2) Å the Ce–N(N3) distance is significantly longer than typical Ce IV –N(amide) bond lengths (e.g. 2.217(3) in[(Me 3 Si) 2 N] 3 CeCl) 9b…”

Ceric Cyclopentadienides Bearing Alkoxy, Aryloxy, Chlorido, or Iodido Co‐Ligands

“…However, only iodine proved to afford complete Ce III →Ce IV oxidation, as shown by the isolation of Ce[N(CH 2 CH 2 NR) 3 ]I . The isolation of Ce[N(SiMe 3 ) 2 ] 3 Cl in moderate yields from the reaction of Ce[N(SiMe 3 ) 2 ] 3 and the rather unusual oxidant TeCl 4 by Lappert and co‐workers marked another breakthrough . Later, the halide complexes Ce[N(SiMe 3 ) 2 ] 3 X (X=F, Br, I) were synthesized by using either Ph 3 CBF 4 and Ph 3 PBr 2 as oxidants or SiMe 3 I in a halogenido exchange reaction.…”