Open AccessCluster Salts [Nb 6 Cl 12 (HIm) 6 ] A n (with HIm=1 H ‐imidazole and A =Mineral Acid Anion, n =1 or 2) Made in and with Brønsted‐basic Ionic Liquids and Liquid Mixtures
Author(s) -
Sperlich Eric,
Köckerling Martin
Publication year - 2021
Publication title -
chemistryopen
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.644
H-Index - 29
ISSN - 2191-1363
DOI - 10.1002/open.202000266
Subject(s) - imidazole , chemistry , octahedron , cluster (spacecraft) , molecule , crystallography , hydrogen bond , ionic liquid , solvent , methanol , formula unit , inorganic chemistry , crystal structure , medicinal chemistry , stereochemistry , organic chemistry , catalysis , computer science , programming language
Four new hexanuclear niobium cluster compounds of the general formula [Nb 6 Cl 12 (HIm) 6 ]( A ) n ⋅ x (solvent molecule) (HIm=1 H ‐imidazole, A =mineral acid anion, Cl − ( n =2) ( 1 ), (SO 4 ) 2− ( n =1) ( 2 ), (CrO 4 ) 2− ( n =1) ( 3 ), and (HAsO 4 ) 2− ( n =1) ( 4 )) were prepared. Their synthesis can be done in basic ionic liquids, which form on the addition of a mineral acid, which also delivers the counter anion for the final cluster compound, to an excess of the 1 H ‐imidazole. Some addition of an auxiliary solvent, like methanol, improves the speed of crystallisation. The cluster unit comprises a hexanuclear Nb 6 unit of octahedral shape with the edges bridged by Cl atoms and the exo sites being occupied by N‐bonded 1 H ‐imidazole ligands. The cluster cation carries sixteen cluster‐based electrons. Between the NH groups of the ligands of the cluster unit, the anions and the co‐crystallised water ( 1 ), or 1 H ‐imidazole and methanol molecules ( 2 , 3 , and 4 ) a network of hydrogen bonds exists.