title: Synthesis, structure, and reaction chemistry of samarium(II), europium(II), and ytterbium(II) complexes of the unsymmetrical benzamidinate ligand [PhC(NSiMe(3))(NC(6)H(3)Pr(i)(2)-2,6)](-).
abstract: Neutral mononuclear lanthanide(II) bis(amidinate) complexes [LnL(2)(THF)(x)] [L = PhC(NSiMe(3))(NC(6)H(3)Pr(i)(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 LnI(2)(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-chalcogenolate complexes [LnL(2)(mu-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 [YbL(2)(SePh)(THF)] (8). The reaction of 5 with iodine led to the Yb(III) bis(amidinate) iodide complex [YbL(2)(I)(THF)] (10). Treatment of 3 with N,N'-dicyclohexylcarbodiimide afforded the mixed-ligand Sm(III) tris(amidinate) [SmL(2){CyNC(H)NCy}] (11) (Cy = cyclohexyl). The molecular structures of complexes 2-5 and 7-11 were elucidated by X-ray diffraction analyses.
authors.affiliation: Department of Chemistry, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong SAR, PR China.
authors.forename: Shuang
authors.initials: S
authors.lastname: Yao
authors.forename: Hoi-Shan
authors.initials: HS
authors.lastname: Chan
authors.forename: Chi-Keung
authors.initials: CK
authors.lastname: Lam
authors.forename: Hung Kay
authors.initials: HK
authors.lastname: Lee