Phosphaniminato-Komplexe des Titans. Synthese und Kristallstrukturen von CpTiCl2(NPMe3), [TiCl3(NPMe3)]2, [Ti2Cl5(NPMe2Ph)3] und [Ti3Cl6(NPMe3)5][BPh4]

Phosphoraneiminato Complexes of Titanium. Synthesis and Crystal Structures of CpTiCl₂(NPMe₃), TiCl₃(NPMe₃)]₂, Ti₂Cl₅(NPMe₂Ph)₃], and Ti₃Cl₆(NPMe₃)₅]BPh₄] The title compounds are formed from Cp₂TiCl₂ and titanium tetrachloride, respectively, and the corresponding phosphane imino compounds Me₃SiNPMe₃ and Me₃SiNPMe₂Ph. The tetraphenyl borate salt yielded from the reaction of Ti₃Cl₆(NPMe₃)₅]Cl with NaBPh₄. All compounds form yellow crystals which are sensitive to moisture. They were characterized by IR-spectroscopy and crystal structure analyses. CpTiCl₂(NPMe₃) ( 1 ): Space group Pbca, Z = 8, solution of the structure with 1632 observed independent reflections, R = 0.037. Lattice dimensions at 19°C: a = 1202.6, b = 1224.2, c = 1766.7 pm. The molecules of the compound are monomeric with the (NPMe₃)^? ligand in almost linear array (bond angle Ti? N? P 170.7°). TiCl₃(NPMe₃)]₂ ( 2 ): Space group Pbca, Z = 8, structure solution with 698 observed independent reflections, R = 0.030. Lattice dimensions at ?60°C: a = 1140.5, b = 1112.2, c = 1589.4 pm. In 2 the titanium atoms, which occur in trigonal bipyramidal coordination, are linked by the N atoms of the (NPMe₃)^? groups to form a centrosymmetric dimer with Ti? N bond lengths of 184.3 and 208.2 pm. Ti₂Cl₅(NPMe₂Ph)₃] · CH₂Cl₂ ( 3 ): Space group Pca2₁, Z = 4, structure solution with 8477 observed independent reflections, R = 0.051. The lattice dimensions at 20°C are: a = 1221.0; b = 1407.5, c = 2139.3 pm. 3 can be understood as a reaction product of TiCl₂(NPMe₂Ph)₂ and TiCl₃(NPMe₂Ph). In the resulting, heavily distorted Ti₂N₂-four-membered ring the Ti? N bond lenghts are 1804., 194.4, 199.2, and 234.6 pm. The longest Ti? N bond is in trans-position to the N atom of the terminal (NPMe₂Ph)- ligand, in which the Ti? N distance is 175.6 pm. .Ti₃CL₆(NPMe₃)₅]BPh₄] (4): Space group P2₁/n, structure solution with 2846 observed independent reflections, R = 0.062. The lattice dimensions at 20°C are: a = 1495.2, b = 2335.4, c = 155,8 pm, β = 93.28°. In the cation of 4 the three titanium atoms along with three (NPMe₃)- groups with μ2- N functions and two (NPMe₃)- groups with μ3- N functions form a nation number 6 with two terminal chlorine atoms.