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Z. Naturforsch. 2014,
69b, 1199 – 1205
doi:10.5560/ZNB.2014-4168
Cyanide and Azide Anion Complexation by a Bidentate Stibonium-Borane Lewis Acid
Department of Chemistry, Texas A&M University, College Station, Texas 77843-3255, USA
Reprint requests to Prof. François P. Gabbaï. E-mail:
francois@tamu.edu
Received August 1, 2014 / published online December 19, 2014
Dedicated to Professor Hubert Schmidbaur on the occasion of his 80th birthday
Our ongoing interest in the chemistry of polyfunctional Lewis acids has led us to investigate the reaction of the stibonium-borane [o-(Ph2MeSb)(Mes2B)C6H4]+ (1+) with cyanide and azide, two toxic anions. Both anions react with 1+ to afford the corresponding neutral complexes 1-CN and 1-N3. Structural and computational studies show that the coordinated anion interacts with both the boron and antimony atoms of the bidentate Lewis acid. While the azide complex features a typical κ2N1:N1 bridging azide ligand, the cyanide complex possesses a cyanoborate moiety whose cyanide interacts side-on with the stibonium center. The Lewis acid–anion interactions
observed in these complexes have also been studied computationally using the Natural Bond Orbital method.
Key words: Lewis Acid, Boron, Antimony, Azide, Cyanide