Supersilylierte Disilene, Cyclotri-, Cyclotetra- sowie Tetrahedrosilane: Erzeugung, Strukturen, Bildungswege

A reactive Si4 cage: K(SitBu3)3Si4

“…Compound 2 is highly sensitive to air and turns green in it. It reacts with methanol or ethanol (ROH) at r.t. to form cis-trans-trisupersilylcyclotrisilane, R* 3 Si 3 H 3 , 3 [6] instead of the expected trisupersilyltetrahedro-tetrasilane, R* 3 Si 4 H, (Scheme 1). Destabilization of the tetrahedron due to steric accessibility caused by the tiny proton facilitates further reaction towards 3 [6].…”

“…1 H NMR (C 6 D 6 , 399.78 MHz, 25°C) d 1.32 (s, 81H, 3R*), 2.58 (AB 2 : 3 J HH = 9.9 Hz, 1H, SiH), 2.77 (AB 2 : 3 J HH = 9.9 Hz, 2H, 2SiH). 29 Si{H} NMR (C 6 D 6 , 79.43 MHz, 25°C) d 29.08 (s, 2R*), 23.73 (s, R*), À153.30 (2 Si-skeletal), À161.20 (1 Si-skeletal) [6]. …”

Cleavage of the Silicon-Silicon and Silicon-Chlorine Bond oftBu3Si-SiCl3

“…Treatment of t Bu 3 Si‐SiCl 3 with an excess of potassium in benzene resulted in an immediate reaction. The 29 Si NMR spectrum showed that t Bu 3 Si‐SiCl 3 had been completely consumed, and new signals appeared which could be assigned to the tetrasilatetrahedrane ( t Bu 3 Si) 4 Si 4 ( 5 ; tetrasupersilyl‐ tetrahedro ‐tetrasilane), the disilane t Bu 3 Si‐Si t Bu 3 , and the silane t Bu 3 SiH. The formation of these products suggested to us the mechanism as shown in Scheme : (i) At first potassium reacts with t Bu 3 Si‐SiCl 3 to give K[Si t Bu 3 ] and K[SiCl 3 ].…”

“…(iii) Reaction of SiCl 2 with K[Si t Bu 3 ] and dimerization of the ( t Bu 3 Si)SiCl thus formed gives the disilene ( t Bu 3 Si)ClSi=SiCl(Si t Bu 3 ). (iv) Dehalogenation of the disilene by reaction with K[Si t Bu 3 ] finally gives the tetrasilatetrahedrane 5 , the disilane t Bu 3 Si‐Si t Bu 3 , and KCl. It is interesting to note that the same products are formed by treatment of HSiCl 3 , Si 2 Cl 6 , or Si 3 Cl 8 with Na[Si t Bu 3 ] .…”

Reaction of [Tris(trimethylsilyl)methyl]tribromogermane with Magnesium: Generation of a Bromogermylene

“…(2) (a)Wiberg, N.; Hochmuth, W.; Nöth, H.; Appel, A.; Schmidt- Amelunxen, M. Angew. (1) (a) Sekiguchi, A.; Kabuto, C.; Sakurai, H. Angew.…”