The first octasilacubane system: synthesis of octakis-(t-butyldimethylsilyl)pentacyclo[4.2.0.02,5.03,8.04,7]octasilane

Abstract

The first octasilacu bane, octakis-(t-butyldimethylsilyl)pentacyclo[4.2.O.O~~~.O~~*.O~~~]octasilane, was synthesised in one step by condensation of 2,2,3,3-tetrabromo-1,4-di-t-butyl-l ,I ,4,4-tetramethyltetrasilane or 1 ,I ,I -tribromo-2-t-butyl-2,2-dimethyldisilane with sodium in toluene.

Cage Compounds of Heavier Group 14 Elements

“…The theory shows that the bond length difference between a and b decreases significantly as M becomes heavier. It is interesting that, in contrast to the theoretical calculations, a is longer than b in Si 6 R 6 [R D 2,6-(i-Pr) 2 …”

“…Despite the obviously great synthetic challenge, such strained polyhedranes of Si, Ge and Sn have not been prepared until recently, and were even considered to be synthetically inaccessible. The first breakthrough in their synthesis occurred in the late 80s, when reports on the synthesis of the first octasilacubane 2 and hexagermaprismane 3 were published in the scientific literature. Then, during the last decade, there was dramatic progress in the chemistry of such cage compounds, and many new derivatives have been prepared.…”

Thermal Reaction of Octasilacubane with Sulfur, Selenium, and Tellurium: Formation of Novel Cage Systems

“…The mechanism of the formation of 5 is not yet determined, but it is quite plausible with that shown in Scheme 3. Usually [2,2] ring-opening is thermally prohibited; however, slightly generated ladder intermediate 6 may promptly react with selenium to give 7. Because of the severe steric hindrance of bulky thexyl groups in 7, skeletal rearrangement might occur to give product 5.…”

A G3(MP2B3) investigation on the structures and properties of silaprismanes

“…The synthesis of the closed ladder polysilanes is challenging. To our knowledge, only the compounds with hexasilaprismane (n = 3) or octasilaprismane (n = 4) frameworks have been synthesized [16][17][18]. Theoretical calculations then provide a useful tool to characterize the structures and properties of these interesting compounds [19][20][21][22][23][24][25].…”