Received 28 October 2012
In the heterometallic title bulky amido complex, [LiNa(C15H21N2Si)2(C6H16N2)], both alkali metal ions are four-coordinated with distorted tetrahedral geometries. The Li+ ion is N,N'-chelated by the N-silylated amido ligand, with Li-N = 2.015 (5) and 2.074 (5) Å. The two amido ligands are arranged cis to each other. The molecule exhibits a twofold rotational symmetry operation along the Li-Na axis. The Na+ ion is coordinated by two N atoms from the tetramethylethylenediamine ligand [Na-N = 2.553 (4) Å] and shares two amido N atoms from the N-silylated amido ligands with the Li+ ion. Although the crystal structure contains voids with an approximate volume of 50 Å3 there is no inclusion of solvent molecules.
For related metal complexes with N-silylated quinolyl amido ligands, see: Engelhardt et al. (1988, 1990, 1991). For silyl-bridged aminoquinoline derivatives, see: Jones et al. (2000). For mixed alkali metal systems as superbase reagents, see: Forbes et al. (2003); Mulvey (2006); Wei et al. (2008).
Data collection: SMART (Bruker, 2000); cell refinement: SAINT (Bruker, 2000); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXL97.
Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: RK2385 ).
This work was supported by grants from the Natural Science Foundation of China (20702029) and the Natural Science Foundation of Shanxi Province (2008011024).
Bruker (2000). SMART and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.
Engelhardt, L. M., Jacobsen, G. E., Junk, P. C., Raston, C. L., Skelton, B. W. & White, A. H. (1988). J. Chem. Soc. Dalton Trans. pp. 1011-1020.
Engelhardt, L. M., Jacobsen, G. E., Junk, P. C., Raston, C. L. & White, A. H. (1990). Chem. Commun. pp. 89-90.
Engelhardt, L. M., Junk, P. C., Patalinghug, W. C., Sue, R. E., Raston, C. L., Skelton, B. W. & White, A. H. (1991). Chem. Commun. pp. 930-931.
Forbes, G. C., Kenley, F. R., Kennedy, A. R., Mulvey, R. E. & O'Hara, C. T. (2003). Chem. Commun. pp. 1140-1141.
Jones, C., Junk, P. C. & Smithies, N. A. (2000). J. Organomet. Chem. 607, 105-111.
Mulvey, R. E. (2006). Organometallics, 25, 1060-1075.
Sheldrick, G. M. (1996). SADABS. University of Göttingen, Germany.
Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.
Wei, X. H., Dong, Q. C., Tong, H. B., Chao, J. B., Liu, D. S. & Lappert, M. F. (2008). Angew. Chem. Int. Ed. 47, 3976-3978.