New Method for the Synthesis of Silaheterocycles and the First Pentacoordinate Silanol

Reactions of the Disilane Me3SiSiCl3 with P‐Chlorophosphaalkenes: Transient and Persistent Per‐Silylated Phosphaalkenes

“…[1] In contrast, synthetic progress to simple dihalogenosilylenes has been very limited since Timms' high-temperature and matrix studies. [2,3] Oligomeric silanes of empirical formula SiCl 2 are synthetically available, but they do not behave as sources of monomeric SiCl 2 , [4] and the alternative use of Si 2 Cl 6 [5] or HSiCl 3 [6] as precursors is very limited. Only very recently, Scheme 1.…”

“…To obtain access to compounds related to the elusive intermediates 2a and 3a from the (Me 3 Si) 2 C=P-Cl/Si 2 Cl 6 reaction, we chose the following experimental variations of the system: 1. Replacement of Si 2 Cl 6 by the unsymmetric disilane Me 3 SiSiCl 3 (5) [analogous to the above-mentioned Me 3 GeSiCl 3 (6)] as a more reactive silylating agent, [8] to allow milder reaction conditions for the generation of the shortlived intermediate 2a. 3 Si groups in (Me 3 Si) 2 C=P-Cl (1a) by bulkier iPrMe 2 Si groups, [14] which are expected to affect the rates of steps II (dimerisation) and III (PǞC 1,3-silyl shift reaction), leading to enhanced lifetimes of intermediates related to 2a and 3a.…”

“…1 H NMR (C 6 Data were recorded using Mo-K α radiation (λ = 0.71073 Å) on an Oxford Diffraction Xcalibur S diffractometer. An absorption correction was based on multi-scans.…”

Dichlorosilylene and dichlorogermylene transfer to alkylidenephosphanes

“…A very useful azadienetype trapping reagent, that would meet these requirement, had been featured by Karsch et al, who ''extract'' a SiCl 2 moitey out of the HSiCl 3 /amine system [24]. As alternative reagents, that combine sufficient nucleophilicity and high reactivity towards carbene-analogous species, we chose a sterically tuned set of P-phosphanylalkylidenephosphanes [25].…”

Ungewöhnliche Spaltung von PC-Bindungen durch doppelten Dichlorsilylen-Transfer von Trichlorsilyltrimethylgerman auf P-Phosphanylphosphaalkene

“…[1] Demgegen¸ber hat es in der Chemie der kurzlebigen Dihalogensilylene in den letzten 30 Jahren seit den Hochtemperatur/Matrix-Untersuchungen von Timms et al kaum Fortschritte gegeben. [2,3] Oligomere Silane der Summenformel SiCl 2 sind zwar pr‰parativ zug‰ng-lich, aber aus ihnen kann kein monomeres SiCl 2 gewonnen werden; [4] Si 2 Cl 6 [5] oder HSiCl 3 [6] sind als Alternativen nur in Einzelf‰llen brauchbar. Wir berichten im Folgenden¸ber die Verwendung von Trichlorsilyltrimethylgerman (Me 3 GeSiCl 3 ) 1 [7,8] als neues Reagens f¸r die ‹bertragung von SiCl 2 -Bausteinen auf P-Phosphanylphosphaalkene unter ‰u˚erst milden Reaktionsbedingungen.…”