Unusual structural features of a siloxane

Abstract

97. 34(3t [97.47(3t] at 300 K [120 K] with Z = 2. Even at 120 K the Si-O-Si fragment is found to be strictly linear due to crystallographically imposed symmetry. To explain the unusual electron distribution derived from the X-ray data collected, several types of possible disorders are discussed, none of which leads to a satisfying explanation. It was found that the lone pairs on the siloxane oxygen were tipped away from cylindrical symmetry. The tipping was directed toward the fluorine substituents on the silicon atoms and away from the CpFe(CO)2 units. A pertubational approach was utilized to rationalize this effect.

Reactions of Hydrosilanes with Transition-Metal Complexes: Formation of Stable Transition-Metal Silyl Compounds

“…Structural data reported for silyl−transition-metal complexes prepared from hydrosilanes and that include only those derivatives with “classical” M−Si, M−H, and/or Si−H bonds are summarized in Table . − …”

“…Si(Fe,Ru,Os) bonds prepared by other methods or preceding 1980 and structurally characterized. SiFe: 2.218(2); 2.222(3); , 2.224(1); 2.2277(14); 2.230(2); 2.2330(14); 2.249(1); , 2.249(3); 2.252(3); 2.258(1); 2.260(6); 2.262(2); , 2.262(1); 2.263(1); 2.263(2), 2.264(2); 2.264(2); 2.265(1); 2.266(3); 2.267(1); 2.268(8); 2.271(4); 2.275(2); 2.278(1); 2.280(3); 2.281(4); 2.285(3); 2.286(5); 2.286(1); 2.287(2); 2.290(3); 2.294(1); 2.296(2); 2.297(3); 2.301(1); 2.303(1); 2.307(1); 2.307(2); 2.310(1); 2.322(1); 2.311(2); 2.311(3); 2.3l3(6); 2.315(2); 2.316(13); 2.322(4); 2.325(3); 2.326(3); 2.327(3); 2.328(1); 2.33(1); 2.330(2); 2.338(4); 2.339(2); 2.339(1); 2.341(2); 2.346; 2.347(1); 2.350(1); 2.354(2); 2.356; 2.356(1); 2.357(3); , 2.364(5); 2.365(2); 2.366(2); 2.366(1); 2.375(2); 2.378(1);…”

Linear Si–O–Si fragments: structure of 1,1,3,3-tetramethyl-1,3-bis[(2-oxo-1-pyrrolidinyl)methyl]disiloxane dihydrochloride and analysis of displacement parameters

“…The analysis was applied to the molecule described in this communication, (2), to (Ph3Si)20, (4) (Glidewell & Liles, 1978), to its benzene and piperidine solvates, (5) and (6) (Suwinska, Palenik & Gerdil, 1986), to [(CO)3CpFe(CH3)(F)Si]20, (7) (Ries, Albright, Silvestre, Bernal, Malisch & Burschka, 1986) all of which occupy a centrosymmetrical position in the crystal, and to Ph3SiO-Si(C2H3)3, (9) (Gusev, Los, Vlasenko, Zhun & Sheludyakev;1984;Gusev, 1991) with crystallographic C3 symmetry. All these structures were determined with reasonable accuracy.…”

“…Ries et al (1986) have argued that, for (7), this inclination is related to the electronegativities of the substituents at Si and that it is a consequence of the valence-electron distribution. In order to test this hypothesis, we have performed a refinement on (2) using 1015 data for which 0 > 20 °.…”

Iron‐Fragment‐Substituted Heterosiloxanes of Gallium [Cp(OC)2Fe−SiR2OGaR′2]2(R, R′ = Alkyl, Aryl) − Structures of [Cp(OC)2Fe−SiR2OGaMe2]2(R = Me, Ph)

“…[22] and lie in the range between a coordinative interaction and a sigma bond. [23] A distorted tetrahedral geometry at the group 13 element is indicated by the angles formed by the ligands of [12] }.…”