Transformation of various multicenter bondings within bicapped-square antiprismatic motifs: Z-rearrangement

0543373 - ÚACH 2022 RIV GB eng J - Journal Article
Bakardjiev, Mario - Holub, Josef - Růžičková, Z. - Růžička, A. - Fanfrlík, Jindřich - Štíbr, Bohumil - McKee, M.L. - Hnyk, Drahomír
Transformation of various multicenter bondings within bicapped-square antiprismatic motifs: Z-rearrangement.
Dalton Transactions. Roč. 50, č. 35 (2021), s. 12098-12106. ISSN 1477-9226. E-ISSN 1477-9234
R&D Projects: GA ČR(CZ) GA19-17156S
Institutional support: RVO:61388980 ; RVO:61388963
Keywords : Bond formation * Molecular rearrangement * Isomerization
OECD category: Inorganic and nuclear chemistry; Physical chemistry (UOCHB-X)
Impact factor: 4.569, year: 2021
Method of publishing: Limited access
https://pubs.rsc.org/en/content/articlelanding/2021/DT/D0DT04225K#!divAbstract

Reported herein are mutual rearrangements in the whole series of seven bicapped-square antiprismatic closo-C2B8H10 by means of high-quality computations that disprove the earlier postulated dsd (diamond-square-diamond) scheme for these isomerizations. The experimentally existing closo-1,2-C2B8H10 was able to be converted to 1,6-, and 1,10-isomers by pyrolysis, and the dsd (diamond-square-diamond) mechanism was offered as an explanation of these processes. However, these computations disprove the postulated dsd scheme for these isomerizations that take place in the ten-vertex closo series. Experimentally observed thermal rearrangements, both in the parent and substituted closo-1,2-C2B8H10, closo-1-CB9H10−, and closo-B10H102−, indirectly support these refined computations. All these processes are based on the new concept of the so-called Z-mechanism, being consistent with a transition state of a boat shape with an open hexagonal belt that results from the initial breakage of three bonds. Such bond breakings and the consequent bond formations bring to mind the shape of the letter Z. In effect, the pattern of multicenter bonding shifts from reactant through a transition state to product. The molecular rearrangements that are available experimentally favour either the axial or equatorial isomers, and this ratio depends on temperature and the type of cluster and its substitution.
Permanent Link: http://hdl.handle.net/11104/0322615


Research data: CCDC, CCDC, RSC Publishing