A stable silicon-based allene analogue with a formally sp-hybridized silicon atom
- 13 February 2003
- journal article
- letter
- Published by Springer Science and Business Media LLC in Nature
- Vol. 421 (6924), 725-727
- https://doi.org/10.1038/nature01380
Abstract
Carbon chemistry exhibits a rich variety in bonding patterns, with homo- or heteronuclear multiple bonds involving sp-hybridized carbon atoms as found in molecules such as acetylenes, nitriles, allenes and carbon dioxide. Carbon's heavier homologues in group 14 of the periodic table—including silicon, germanium and tin—were long thought incapable of forming multiple bonds because of the less effective pπ–pπ orbital overlap involved in the multiple bonds. However, bulky substituents can protect unsaturated bonds and stabilize compounds with formally sp-hybridized heavy group-14 atoms1,2: stable germanium2, tin3 and lead4 analogues of acetylene derivatives and a marginally stable tristannaallene5 have now been reported. However, no stable silicon compounds with formal sp-silicon atoms have been isolated. Evidence for the existence of a persistent disilaacetylene6 and trapping7 of transient 2-silaallenes and other X = Si = X′ type compounds (X, X′ = O, CR2, NR, and so on) are also known, but stable silicon compounds with formally sp-hybridized silicon atoms have not yet been isolated. Here we report the synthesis of a thermally stable, crystalline trisilaallene derivative containing a formally sp-hybridized silicon atom. We find that, in contrast to linear carbon allenes, the trisilaallene is significantly bent. The central silicon in the molecule is dynamically disordered, which we ascribe to ready rotation of the central silicon atom around the molecular axis.Keywords
This publication has 11 references indexed in Scilit:
- Synthesis and Characterization of a Digermanium Analogue of an AlkyneAngewandte Chemie-International Edition, 2002
- Synthesis, Structure and Dehalogenation of the Disilene RClSi=SiClR [R = (tBu3Si)2MeSi]European Journal of Inorganic Chemistry, 2002
- Synthesis and Characterization of 2,6-Dipp2-H3C6SnSnC6H3-2,6-Dipp2 (Dipp = C6H3-2,6-Pri2): A Tin Analogue of an AlkyneJournal of the American Chemical Society, 2002
- Invisible but Common Motion in Organic Crystals: A Pedal Motion in Stilbenes and AzobenzenesJournal of the American Chemical Society, 2001
- Stable Systems with a Triple Bond to Silicon or Its Homologues: Another ChallengeAngewandte Chemie-International Edition, 2000
- Heavy Allenes and Cumulenes ECE‘ and ECCE‘ (E = P, As, Si, Ge, Sn; E‘ = C, N, P, As, O, S)Chemical Reviews, 2000
- Synthesis and Characterization of 2,6-Trip2H3C6PbPbC6H3-2,6-Trip2 (Trip = C6H2-2,4,6-i-Pr3): A Stable Heavier Group 14 Element Analogue of an AlkyneJournal of the American Chemical Society, 2000
- The First Isolable DialkylsilyleneJournal of the American Chemical Society, 1999
- Tetrasupersilyl-tristannaallene and -tristannacyclopropene (tBu3Si)4Sn3 – Isomers with the Shortest Sn=Sn Double Bonds to DateEuropean Journal of Inorganic Chemistry, 1999
- High-pressure synthesis, structure and novel photochemical reactions of 7,7,8,8-tetramethyl-7,8-disilabicyclo[2.2.2]octa-2,5-dieneJournal of the Chemical Society, Chemical Communications, 1991