Synthesis and characterisation of novel zirconium(iv) derivatives containing the bis-amido ligand SiMe2(NRR′)2

Unsymmetrically Substituted Dimethyldiaminosilanes as Ligands towards Zirconium(IV)

“…As alluded to in the introduction, the binary species Zr[SiMe 2 (NR) 2 ] 2 adopts a different molecular structure (both in the solid state and in solution) depending on the identity of R (R ϭ iPr, dimer; [3] R ϭ tBu, monomer [5] ) and elsewhere [3] we proposed that the different steric hindrances of iPr and tBu should be responsible for this observation. Therefore, elucidation of the molecular structure of Zr[SiMe 2 (NtBu)(NiPr)] 2 (12) appeared interesting.…”

“…Examples of the zirconium systems include, i) Zr(NMe 2 ) 4 reacts with SiMe 2 (NHR) 2 yielding Zr(NMe 2 ) 3 (NHMe 2 )[SiMe 2 (NtBu)(NHtBu)] [3] or Zr(NMe 2 ) 2 (NHMe 2 )[SiMe 2 (NPh) 2 ] (Ph ϭ 2,6-Me 2 C 6 H 3 );…”

“…For instance, the above mentioned tert-butyl derivative Zr[SiMe 2 (NtBu) 2 ] 2 is volatile, [5] while the isopropyl analogue decomposes at about 430 K without subliming. [3] Based on this background, it seemed interesting to enlarge the class of dimethyldiaminosilanes and their metal complexes and, since little [6Ϫ8] is known about the ligating ability of unsymmetrically substituted diaminosilanes, we have pursued a) the synthesis of novel compounds of this class (eventually containing additional ligating sites) (Scheme 1, IIϪIII) and b) the investigation of their ligating properties towards zirconium().…”

“…ii) the binary amido derivative Zr[SiMe 2 (NR) 2 ] 2 is a dimer when R ϭ iPr [3] and a monomer when R ϭ tBu. [5] Moreover, as a consequence of the different structures, different physical and/or chemical properties are observed and expected for the metal derivatives.…”

The crystal structure of 2-chloro-1,3-bis(2,4,6-trimethylphenyl)-4,4-dimethyl-1,3,2λ3,4-diazaphosphasiletidine

“…Their synthesis was rst described more than 50 years ago [1] while their reaction and coordination behavior has been extensively studied during the following years [2][3][4][5][8][9][10][11][12]. Particularly diazaphosphasiletidines resulting from this versatile silylamine precursors have attracted considerable attention in phosphorus chemistry [2][3][4][5].…”