Synthesis and structure of fluorophenyl derivatives of the 10-vertex monocarbaborane anions [1-CB9H10]− and [2-CB9H10]

• Published in: Journal of fluorine chemistry 2012-10, Vol.142, p.14-18
• Main Authors: Bragin, Vikentii I., Korlyukov, Alexander A., Petrovskii, Pavel V., Sivaev, Igor B., Bregadze, Vladimir I.
• Format: Article
• Language: English
• Subjects: Anions; Crystal structure; Derivatives; Diffraction; Fluorophenyl carba-closo-decaborates; Heating; NMR spectroscopy; Synthesis; Synthesis (chemistry); X-ray structure; X-rays
• ISSN: 0022-1139; 1873-3328
• DOI: 10.1016/j.jfluchem.2012.06.019

The C-fluorophenyl-substituted monocarbaborane anions [1-(X-FC6H4)-1-CB9H9]− and [1-(X-FC6H4)-1-CB9H9]− (X=2, 3, 4) were prepared starting from decaborane and the corresponding fluorobenzaldehydes using the Brellochs reaction. [Display omitted] ► New fluoroaryl carboranes [2-(X-FC6H4)-2-CB9H9]− (X=2, 3, 4) have been synthesized. ► On heating 2-arylcarboranes rearrange to 1-arylcarboranes [1-(X-FC6H4)-1-CB9H9]−. ► Structures of the prepared fluoroaryl carboranes were determined by X-ray diffraction. Reactions of decaborane nido-B10H14 with a series of fluorobenzaldehydes in alkaline solution followed by treatment with iodine give the closo-[2-(X-FC6H4)-2-CB9H9]− anions (X=2, 3, 4). Upon heating, these compounds rearrange to more thermodynamically stable closo-[1-(X-FC6H4)-1-CB9H9]− anions (X=2, 3, 4). The compounds synthesized were characterized by multinuclear NMR spectroscopy. The crystal structures of (Bu4N)[1-(2-FC6H4)-1-CB9H9] and (Bu4N)2[2-(4-FC6H4)-2-CB9H9][1-(4-FC6H4)-1-CB9H9] were determined by single crystal X-ray diffraction.