Lithium Zincate, Heteroleptic Triorganylzincate, Zincate, X-Ray, NMR Spectra Bis(trimethylsilylmethyl)-, bis[bis(trimethylsilyl)methyl]-as well as bis (2,2,4,4,6,6-hexamethyl-2,4,6-trisila-cyc/o-hexyl)zinc react with methyl lithium or phenyl lithium in the pres ence of the tridentate l,3,5-trimethyl-l,3,5-triazinane (TMTA) to yield zincates of the type LiZnR2R'-2TMTA. The compounds are colorless and insoluble in aliphatic or aromatic hydrocarbons. These zincates exist in solution as well as in the crystalline state as separated ions, as confirmed for lithium-methyl-bis(2,2,4,4,6,6-hexamethyl-2,4,6-trisila-cyc/o-hexyl)-zincate• 2TMTA by X-ray diffraction (PI; a -1139,5(3); b = 1482,4(4); c = 1528,6(5) pm; a = 95,33(2); ß = 100,13(2); y = 106,91(2)°; Z = 2). The lithium cation is six-coordinated by two TMTA ligands in a distorted anti-prismatic complex. The zinc atom displays a trigonal planar coordination with Z n -C bond lengths of 207 pm to the 2,2,4,4,6,6-hexamethyl-2,4,6-trisila-cyc/o-hexyl ligands and of 202 pm to the methyl group. One trisila-cyc/o-hexyl substi tuent exists in the chair, the other one in the twist conformation. The reaction of lithium bis(trimethylsilyl)amide with bis(trimethylsilylmethyl)zinc yields the benzene soluble lithium-bis(trimethylsilyl)amino-bis(trimethylsilylmethyl)zincate TMTA. The molecular structure was confirmed by X-ray diffraction a -1024,8(3); b = 1775,4(7), c = 1918,2(8) pm; Z = 4). The bridging bis(trimethylsilyl)amino ligand displays long Z n -N and L i-N distances of 213 and 208 pm, respectively, due to the steric inter-ligand repulsion. During the reaction of lithium bis(trimethylsilyl)amide with bis[bis(trimethylsilyl)methyl]-zinc no zincate formations observed. The decomposition products lithium bis(trimethylsilyl)-methanide and the heteroleptic bis(trimethylsilyl)amino-bis(trimethylsilyl)methylzinc were detected.Einleitung