Synthesis, structure, and reaction chemistry of samarium(ii), europium(ii), and ytterbium(ii) complexes of the unsymmetrical benzamidinate ligand [PhC(NSiMe3)(NC6H3Prl2-2,6)] -

Article abstract of DOI:10.1021/ic901327m

Neutral mononuclear lanthanide(II) bis(amidinate) complexes [LnL ₂(THF)_x] [L = PhC(NSiMe₃)(NC₆H ₃Pr^′₂-2,6)^-; Ln = Sm, x = 2 (3); Ln = Eu, x = 2, (4); Ln = Yb, x = 1 (5)] were synthesized by the reaction of the appropriate Lnl2(THF)₂ with potassium amidinate [KL] _n (2). The reduction chemistry of 3-5 was also examined. The reaction of the Sm(II) and Eu(II) amidinates 3 and 4 with diphenyl dichalcogenides PhEEPh (E = Se, Te) led to the binuclear lanthanide(III) amidinate- chalcogenolatecomplexes [LnL₂(μ-EPh)]₂ [Ln = Sm, E = Se (6); Ln = Eu, E = Se (7); Ln = Sm, E = Te (9)], whereas reacting the Yb(II) bis(amidinate) 5 with PhSeSePh yielded the mononuclear [YbL₂(SePh) (THF)] (8). The reaction of 5 with iodine led to the Yb(III) bis(amidinate) iodide complex [YbL₂(I)(THF)] (10). Treatment of 3 with N,N′-dicyclohexylcarbodiimide afforded the mixed-ligand Sm(III) tris(amidinate) [SmL₂{CyNC(H)NCy}] (11) (Cy = cyclohexyl). The molecular structures of complexes 2-5 and 7-11 were elucidated by X-ray diffraction analyses.