Online-Ressource | |
Verfasst von: | Monakhov, Kirill [VerfasserIn] |
Zessin, Thomas [VerfasserIn] | |
Linti, Gerald W. [VerfasserIn] | |
Titel: | Reduction vs. metathesis in the reactions of bismuth tribromide with a bulky lithium silanide |
Titelzusatz: | an experimental and theoretical study |
Verf.angabe: | Kirill Yu. Monakhov, Thomas Zessin, and Gerald Linti |
E-Jahr: | 2010 |
Jahr: | 04 January 2010 |
Umfang: | 11 S. |
Fussnoten: | Gesehen am 03.05.2023 |
Titel Quelle: | Enthalten in: European journal of inorganic chemistry |
Ort Quelle: | Weinheim : Wiley-VCH, 1998 |
Jahr Quelle: | 2010 |
Band/Heft Quelle: | (2010), 2, Seite 322-332 |
ISSN Quelle: | 1099-0682 |
Abstract: | On reaction of BiBr3 with Li(thf)3SiPh2tBu (1) in the corresponding ratios redox/metathesis reactions were observed, yielding dibismuthane (tBuPh2Si)4Bi2 (2) and disilylbismuth halide (tBuPh2Si)2BiBr (3). The latter is a reaction intermediate in the formation of the dark-red 2. The X-ray crystal structures of 1-3 were determined by low-temperature X-ray diffraction. The Si2Bi-BiSi2 core of 2 is in the semi-eclipsed conformation. No oligomerization of “nonthermochromic” 2 was observed. Compound 3 is a mixed substituted monomer with a pyramidal environment around the bismuth center. On the basis of quantum chemical calculations, the formation of tertiary bismuthane (tBuPh2Si)3Bi is not expected for steric reasons. According to DFT-optimized geometries of the simplified model systems n[(H3Si)2Bi]2 (n = 1-3), the closed-shell attraction between intermolecular Bi centers in the chain provides a moderate elongation of the intramolecular Bi-Bi bond in the dibismuthane unit and a shortening of the intermolecular Bi···Bi contacts. According to MP4(SDQ) computations, such oligomerization is carried out by intermolecular interaction of s lone pairs that are bound together and p-type orbitals of the Bi-Bi bonds in the bismuth chain. An increase in the number of [(H3Si)2Bi]2 molecules per chain results in a decrease in the HOMO-LUMO gap and leads to a bathochromic shift. TD-PBE0 computations suggest that the lowest energy electron transition in 2 is metal-metal charge transfer. In addition, the attractive contributions in the chain [(H3A)2Bi]2···[Bi(AH3)2]2 with silyl groups (A = Si) outweigh the repulsion of the Bi···Bi centers, whereas for the alkyl-substituted bismuth chain (A = C) the repulsive van der Waals force dominates. This fact makes the rectangle oligomerization model more preferred for n[(H3A)2Bi]2 (A = C; n = 2), while for A = Si chain formation is favored in the gas phase. |
DOI: | doi:10.1002/ejic.200900773 |
URL: | Bitte beachten Sie: Dies ist ein Bibliographieeintrag. Ein Volltextzugriff für Mitglieder der Universität besteht hier nur, falls für die entsprechende Zeitschrift/den entsprechenden Sammelband ein Abonnement besteht oder es sich um einen OpenAccess-Titel handelt. Volltext: https://doi.org/10.1002/ejic.200900773 |
Volltext: https://onlinelibrary.wiley.com/doi/abs/10.1002/ejic.200900773 | |
DOI: https://doi.org/10.1002/ejic.200900773 | |
Datenträger: | Online-Ressource |
Sprache: | ger |
Sach-SW: | Bismuth |
Crystal structure analysis | |
Density functional calculations | |
Lithium | |
Silicon | |
K10plus-PPN: | 184445682X |
Verknüpfungen: | → Zeitschrift |