Ein molekularer Siliciumcluster mit einem “nackten” Gerüstatom

N‐Heterocyclic Carbene Coordinated Neutral and Cationic Heavier Cyclopropylidenes

“…To this end, our first choice as a precursor was disilenide 9, [24] because of its versatile reactivity towards halosilanes. [25] We anticipated that the reduction of an initial substitution product at the Si IV center would give [10], which in analogy to the Si 2 Ge system could isomerize via [11] to afford 12. Computations at the wB97XD/6-311G(d,p) level of theory identified each step of this sequence to be exergonic ([10]!…”

An Organosilicon Cluster with an Octasilacuneane Core: A Missing Silicon Cage Motif

“…[1] Therefore, synthetic studies on organosilicon clusters have been extensively developed. Persilapolyhedranes, [2][3][4] decasilaadamantane, [5] pentasila[1.1.1]propellane, [6] persila[n]staffane (catenated silicon cages), [7] and related siliconoids [8,9] have all been shown to possess unique electronic characteristics owing to developed s conjugation among the caged SiÀSi bonds. Octasilacuneane, a silicon analog of cuneane [10] (pentacyclo[3.3.0.0 2,4 .0 3,7 .0 6,8 ]octane), is a missing saturated silicon cluster motif, but potentially important because octasilacuneane is an isomeric silicon cage of octasilacubane, [4] one of the most well-known silicon polyhedra.…”

Pentagerma[1.1.1]propellane: A Combined Experimental and Quantum Chemical Study on the Nature of the Interactions between the Bridgehead Atoms

“…[17] Seminal work was performed by Sita and Kinoshita in the early 1990s; they succeeded in isolating the pentastanna-[1.1.1]propellane [Sn 5 R 6 ] (A) and the derivative [Sn 7 R 8 ] (B, R = 2,6-Et 2 C 6 H 3 ). To date, however, metallapropellanes solely composed of silicon [21] or germanium [22] atoms are unknown, and experimental studies on the reactivity of metallapropellanes are still in their infancy. Structurally characterized compounds such as [Sn 5 R 6 ] (C, R= 2,6-(iPrO) 2 C 6 H 3 ) and [Ge 2 {Sn(Cl)R} 3 ] (D, R = 2,6-Mes 2 C 6 H 3 ) were reported later by the groups of Drost [19] and Power, [20] respectively.…”

“…Structurally characterized compounds such as [Sn 5 R 6 ] (C, R= 2,6-(iPrO) 2 C 6 H 3 ) and [Ge 2 {Sn(Cl)R} 3 ] (D, R = 2,6-Mes 2 C 6 H 3 ) were reported later by the groups of Drost [19] and Power, [20] respectively. To date, however, metallapropellanes solely composed of silicon [21] or germanium [22] atoms are unknown, and experimental studies on the reactivity of metallapropellanes are still in their infancy. To shed more light on the accessibility and stability of metallapropellanes of this type and to investigate fundamental aspects of their bonding, we have specifically synthesized the first pentagerma[1.1.1]propellane [Ge 5 Mes 6 ] (1)-one of the missing members within the Group 14 element series closing the gap to the theoretical predictions and discussions.…”