Differing coordination environments in transition metal derivatives of 1,8-bis(silylamido)naphthalene ligands.

ABSTRACT

Four low-coordinate transition metal amido complexes featuring sterically demanding 1,8-bis(silylamido)naphthalene ligands are reported. Reaction of one molar equivalent of 1,8-C(10)H(6)(NLiSiMe(3))(2) with ZnCl(2) yields the structurally authenticated dimer [1,8-C(10)H(6)(NSiMe(3))(2)Zn](2) (1), where the 1,8-bis(silylamido)naphthalene moiety is acting as both a chelating and bridging ligand. The effect on the resulting transition metal complexes of increasing the steric demands of the ligand was investigated, using the triisopropylsilyl-substituted ligand 1,8-C(10)H(6)(NSi(i)Pr(3))(2). Reaction of one molar equivalent of 1,8-C(10)H(6)(NLiSi(i)Pr(3))(2) with ZnCl(2) or FeCl(2)(THF)(1.5) yields 1,8-C(10)H(6)(NSi(i)Pr(3))(2)M(mu-Cl)Li(THF)(3) (M = Zn, 2; M = Fe, 3), respectively; the coordination of the ClLi(THF)(3) moiety to the metal center in these compounds is a rare structural motif in the coordination chemistry of the d-block elements. Analogous reaction of 1,8-C(10)H(6)(NLiSi(i)Pr(3))(2) with MnCl(2) affords the mixed-metal Li-Mn-amido complex 1,8-C(10)H(6)(NSi(i)Pr(3))(2)Li(THF)MnCl(THF) (4) which features an unusual LiMnN(2) core.