108148-64-7

Upstream product

• 108148-59-0 3-(tert-Butyldimethylsilyl)-4,4-dimethyl-5,5-bis(trimethylsilyl)-1,2,3-triaza-4-sila-1-cyclopenten 
• 137363-32-7 trans-1-(tert-butyldimethylsilyl)-2,2-dimethyl-4-phenyl-3-isopropyl-1-aza-2-sila-cyclobutane 

Relevant academic research and scientific papers

X-ray structural analysis and thermal decomposition of 1-Aza-2-silacyclobutanes: A new route to silanimine species

X-ray structural analysis of a 1-aza-2-silacyclobutane derivative, trans-1-(tert-butyldimethylsilyl)-2,2,4-triphenyl-3-isopropyl-1-aza-2- silacyclobutane (1), has been carried out for the first time. The 1-aza-2-silacyclobutane skeleton is of small angle strain, being nonplanar in relation to the nearly planar nitrogen atom, and has normal bond lengths, aside from the considerably long C-N bond. 1-Aza-2-silacyclobutanes undergo thermal decomposition around 200 °C in toluene to form a silanimine species, R2S=NR, and an olefin. The formation of silanimine has been confirmed by quantitative formation of the dimer and a 1:1 adduct with Me3SiOEt in the copyrolysis. The 3,4-trans and -cis isomers form trans and cis olefins, respectively. The decomposition rates obey the first-order rate law and decrease in the order 3,4-trans > 3,4-cis > 3,3,4-trisubstituted derivatives. The results are analyzed by the concerted [2s + 2a] cycloreversion mechanisms.

Preparation of Silan- and Germanimines Me2E=NR (E = Si, Ge) from Sila- and Germadihydrotriazoles

Sila- or germaethene Me2E=C(SiMe3)2 quantitatively react with azidoalkanes or -silanes RN3 nMe3-nSi, Ph3Si, (Me3Si)2NMe2E, Me2SiN3> at -78 deg C by cycloaddition to form sila- or germadihydrotriazoles 3 and 4, respectively.The latter decompose partly below (E = Si, R = silyl), partly at or above room temperature (E = Si, R = alkyl; E = Ge) in a first-order reaction by isomerization into diazomethane derivatives as well as by cycloreversion into (Me3Si)2C=N=N and silan- or germanimines Me2E=NR (rate constants: Table 1).The saturated compounds Me2E= NR are formed as short-lived intermediates.Their stabilization, as a rule, takes place by dimerization and, in exceptional cases, by reaction with the silan- or germanimine sources (R = SiMe3) or by intramolecular migration processes .