0466309 - ÚACH 2017 RIV US eng J - Journal Article
Tok, Oleg L. - Růžičková, Z. - Růžička, A. - Hnyk, Drahomír - Štíbr, Bohumil
Prototropic mu-H-8,H-9 and mu-H-9,H-10 Tautomers Derived from the [nido-5,6-C2B8H11](-) Anion.
Inorganic Chemistry. Roč. 55, č. 20 (2016), s. 10122-10124. ISSN 0020-1669. E-ISSN 1520-510X
R&D Projects: GA ČR(CZ) GA16-01618S
Institutional support: RVO:61388980
Keywords : tautomers
Subject RIV: CA - Inorganic Chemistry
Impact factor: 4.857, year: 2016

Reported is an unusual tautomeric behavior within the [nido-5,6-C2B8H11](-) (1a(-)) cage that has no precedence in the whole area of carborane chemistry. Isolated were two skeletal tautomers, anions [6-Ph-nido-5,6-C2B8H10-mu(8,9)](-) (2d(-)) and [5,6-Me-2-nido-5,6-C2B8H9-mu(9,10)](-) (3b(-)), which differ in the positioning of the open face hydrogen bridge. Their structures have been determined by X-ray diffraction analyses. The 3b(-) structure is stabilized by intermolecular interaction involving Et3NH+ and B8-B9 and H8 atoms in the solid phase; however, its dissolution in CD3CN causes instant conversion to the more stable [5,6-Me-2-nido-5,6-C2B8H9-mu(8,9)](-) (2b(-)) tautomer. The dynamic electron-correlation-based MP2/6-31G* computations suggest that the parent [nido-5,6-C2B8H11-mu(8,9)](-) (2a(-)) tautomer is 3.9 kcal center dot mol(-1) more stable than the [nido-5,6-C2B8H11-mu(9,10)](-) (3a(-)) counterpart and the mu(8,9) structure 2(-) is therefore the most stable tautomeric form in the solution, as was also demonstrated by multinuclear (H-1, B-11, and C-13) NMR measurements on the whole series of C-substituted compounds.
Permanent Link: http://hdl.handle.net/11104/0264640


Research data: ACS publications