Heterobimetallic (Imido)antimony/Lithium Cages Containing [Sb(NR)(3)](3-) Trianions

The reactions of [Sb(NMe(2))(3)] with the primary (amido)lithiums [PhCH(2)CH(2)N(H)Li](n)(), [CyN(H)Li](n)() (Cy = C(6)H(11)), [2,4-dmpN(H)Li](n)() [2,4-dmp = 2,4-(MeO)(2)C(6)H(3)], and [(t)()BuN(H)HLi](n)() give the heterobimetallic cage complexes [{Sb(NCH(2)CH(2)Ph)(3)}(2)Li(6).2THF] (1), [{Sb(NCy)(3)}(2)Li(6).2HNMe(2)].2C(6)H(5)CH(3) (2), [Sb{N(2,4-dmp)}(3)](2)Li(6).2THF.2C(6)H(5)CH(3) (3), and [{Sb(NBu(t)())(3)}(2)Li(6)] (4), respectively. The low-temperature X-ray structures of 1-4 show that they are composed of 14-membered polyhedral cages constructed from the association of two [Sb(NR)(3)](3)(-) trianions with six Li(+) cations. Crystal data; 2, triclinic, P&onemacr;, a = 12.775(6) Å, b = 13.191(9) Å, c = 11.015(5) Å, alpha = 111.55(4) degrees, beta = 95.39(4) degrees, gamma = 115.26(4) degrees; 3, triclinic P&onemacr;, a = 10.435(4) Å, b = 12.654(5) Å, c = 14.278(6) Å, alpha = 75.31(4) degrees, beta = 79.33(4) degrees, gamma = 84.33(4) degrees; 4, monoclinic P2(1)/c, a = 9.994(1) Å, b = 17.421(2) Å, c = 10.680(2) Å, beta = 111.33(1) degrees (the structure of 1 being reported previously). Lewis base solvation of the N(6)Li(6) substructures of 1-3 results in distortion and deformation of the Li frameworks. The structural variations in the cores of 1-4 indicate that the bonding in these species is dominated by the valence and bonding demands of the p block metal centers.