Expanding the structural chemistry of the weakly coordinating closo-carborane CB11H12 (-): its monoiodo derivatives with and without C (5v) symmetry

0397185 - ÚACH 2014 RIV US eng J - Článek v odborném periodiku
Hnyk, Drahomír - Holub, Josef - Růžička, A. - Padělková, Z. - Bühl, M.
Expanding the structural chemistry of the weakly coordinating closo-carborane CB11H12 (-): its monoiodo derivatives with and without C (5v) symmetry.
Structural Chemistry. Roč. 24, č. 3 (2013), s. 927-932. ISSN 1040-0400. E-ISSN 1572-9001
Grant CEP: GA ČR GAP208/10/2269
Institucionální podpora: RVO:61388980
Klíčová slova: Weakly-coordinating anions * X-Ray diffraction * B-11 Chemical shifts * Spin-orbit coupling * Acidity
Kód oboru RIV: CA - Anorganická chemie
Impakt faktor: 1.900, rok: 2013

Two iodo derivatives of closo-CB11H12 (-), i.e., 12-I-1-CB11H11 (-) (C (5v) symmetry) and 7-I-1-CB11H11 (-) (C (s) symmetry), were prepared (the latter for the first time) and the influence of differently positioned iodine substituents on the geometry of the CB11 icosahedral core was structurally examined both by X-ray diffraction and quantum-chemical computation at the MP2 level. Observed and computed molecular geometries are in overall agreement. Supramolecular architectures of these two anionic substituted monocarboranes are shown. According to DFT computations at the ZORA-SO/BP86 level, the B-11 chemical shifts of the boron atoms to which iodine substituents are bonded are dominated by spin-orbit coupling. Different positions of iodine atoms in these two isomers may result in different acidities of the (C)-H atoms in the icosahedral bodies, as suggested by visually analyzing the corresponding lowest unoccupied molecular orbitals.
Trvalý link: http://hdl.handle.net/11104/0224818