Silylen‐Reaktionen mit Selenophen und einem Tellurophen: Bildung und Strukturen eines 1,3‐Diselena‐2,4‐disiletans und eines 1,3‐Ditellura‐2,4‐disiletans [1]

Abstract

Photolytisch aus Hexa‐tert‐butylcyclotrisilan erzeugtes Di‐tert‐butylsilylen reagiert mit Selenophen oder 2,5‐Dimethyltellurophen unter Chalkogenabstraktion zum 1,3‐Diselena‐2,4‐disiletan 6 und 1,3‐Ditellura‐2,4‐disiletan 7. Die Röntgenstrukturanalysen von 6 und 7 zeigen das Vorliegen planarer Vierringe mit den kleineren endocyclischen Winkeln an den Chalkogen‐ und den größeren an den Siliciumatomen.

Dimeric and trimeric diorganosilicon chalcogenides (PhRSiE)2,3 (E=S, Se, Te; R=Ph, Me)

“…The value of 1 J SiSe in 2b is in the range of the previously reported values of 106 and 87.5 Hz in the four-membered ring compounds t Bu 2 Si(Se) 2 Si t Bu 2 [18], and (Me 3 Si) 2 Si(Se) 2 Si(SiMe 3 ) 2 [14]. On the other hand the value of 1 J SiSe in 2a fits to the values of 128.3 Hz in Me 2 Si(Se) 2 Si 2 Me 4 (five-membered ring) [23], 133.6 Hz in Me 2 Si(Se) 2 Si 3 Me 6 , 138.5 Hz in PhMeSi(Se) 2 Si 3 Me 6 , and 141.5 Hz in Ph 2 Si(Se) 2 -Si 3 Me 6 (six-membered rings) [24].…”

“…Several compounds of this type have also been obtained by reactions of silylenes with elemental chalcogens or chalcogen transfer reagents 0022-328X/$ -see front matter Ó 2004 Elsevier B.V. All rights reserved. doi:10.1016/j.jorganchem.2004.06.068 [15][16][17][18]. The molecular structures of (R 2 SiE) 2 always show planar four-membered rings Si 2 E 2 with small bond angles (81-85°) at the chalcogen atoms [14][15][16]19].…”

Gas-phase formation of SiSe in IR laser-co-decomposition of dimethyl selenide and 1,3-disilacyclobutane

“…Thus, silene [5][6][7] and silylene [8,9] were detected in the IRMPD of DSCB, and silene and methylsilylene are known [16,17] to exist in thermal equilibrium. Reaction (a) was postulated in our previous work [3] as a step analogous to addition of 3 O 2 to silene [1,18], reaction (b and h) was reported [19][20][21][22] for kinetically stabilized silylenes, and reaction sequences (c, e and d, f) get support from the previous observation of H 2 Se and CH 3 SeH products [3] and similarity to reactions of silylene with 3 O 2 [23]. However, the dimerization of Se atoms (facilitated by third body stabilization) is in the used low pressure region (0.3 mbar) less probable, which gives more support to reactions initiated by Se atoms (steps b, g and h) than those initiated by Se 2 species.…”

Reactions of a Cyclotrisilane with Chalcogen Transfer Reagents [1]

“…The corresponding telluradisilirane was obtained from the reaction of tetramesityldisilene with tellurium [8]. Finally, photolysis of 1 in the presence of a tellurophene afforded a four-membered ring, the 1,3-ditellura-2,4-disiletane system [9]. Thus, compound 5 supplements the series of structurally characterized smaller rings based on silicon and tellurium atoms.…”