Silazanes plus MCl4-substitution vs. rearrangement reactions

Abstract

lead to a large variety of products due to the competition of substitution reactions and ring contractions. The resulting new compounds were characterized by elemental analyses, NMR spectroscopy, and single crystal X-ray structure analyses.

Synthesis and Characterization of Novel Titanium, Germanium, and Tin Silazane Complexes Bearing a Cyclohexasilazanetriido Ligand

“…Furthermore, the reaction pathway was almost unaffected by the type of solvent used. The reaction of Li(HMCTS)H 2 with tin tetrachloride in a ratio of 2:1 yields the substitution product dichlorobis(2,2,4,4,6,6-hexamethylcyclotrisilazano)-stannane, as we reported recently (Scheme 2, route A), [17] but a complex analogous to 1 or 2 was not found. Complex 3, which exhibits the same molecular structure as 1 and 2, was synthesized by reacting H 3 (HMCTS) with 3 equiv.…”

“…The 29 Si resonance of the silazane starting material quickly disappears after the start of the reaction, and new resonance signals ranging from 10 to 15 ppm arise in the spectra. They can be assigned to silicon atoms of (Si-N) 2 rings [17] and indicate cyclodisilazanes as intermediates in the formation of the dodecamethylcyclohexasilazane ring, which is found in complexes 1-3. During the reaction, the intensities of the resonance signals between 10 and 15 ppm decrease, and simultaneously, the 29 Si resonance of the titanium complex 1 appears at δ = -7 ppm.…”

Synthesis of chelating diamido Sn(iv) compounds from oxidation of Sn(ii) and directly from Sn(iv) precursors

“…3 Molecular structures were determined by X-ray crystallography for the five-membered ring dichlorotin species [SnCl 2 (κ 2 -N( t Bu)Si 2 Me 4 N( t Bu)] and also the ferrocenophane [SnCl 2 (κ 2 -N(SiMe 3 )C 5 H 4 FeC 5 H 4 N(SiMe 3 )]. 4 Two additional molecular structures of non-chelating diamidodichlorotin species are also known; [SnCl 2 {N(SiPhMe 2 ) 2 } 2 ] and [SnCl 2 -{N(SiMe 2 NH) 2 SiMe 2 } 2 ], 5 however, for such potentially useful starting materials, relatively little is known about their chemistry. Oxidation reactions of tin(II) compounds are now an extensively studied area.…”