We use cookies to ensure that we give you the best experience on our website. By continuing to browse this repository, you give consent for essential cookies to be used. You can read more about our Privacy and Cookie Policy.

Durham Research Online
You are in:

Syntheses and reductions of C-dimesitylboryl-1,2-dicarba-closo-dodecaboranes.

Kahlert, J. and Böhling, L. and Brockhinke, A. and Stammler, H.-G. and Newmann, B. and Rendina, L.M. and Low, P.J. and Weber, L. and Fox, M.A. (2015) 'Syntheses and reductions of C-dimesitylboryl-1,2-dicarba-closo-dodecaboranes.', Dalton transactions., 44 (21). pp. 9766-9781.


Two C-dimesitylboryl-1,2-dicarba-closo-dodecaboranes, 1-(BMes2)-2-R-1,2-C2B10H10 (1, R = H, 2, R = Ph), were synthesised by lithiation of 1,2-dicarba-closo-dodecaborane and 1-phenyl-1,2-dicarba-closo-dodecaborane, respectively, with n-butyllithium and subsequent reaction with fluorodimesitylborane. These novel compounds were structurally characterised by X-ray crystallography. Compounds 1 and 2 are hydrolysed on prolonged exposure to air to give mesitylene and boronic acids 1-(B(OH)2)-2-R-1,2-C2B10H10 (3, R = H, 4, R = Ph respectively). Addition of fluoride anions to 1 and 2 resulted in boryl-carborane bond cleavage to give dimesitylborinic acid HOBMes2. UV absorption bands at 318–333 nm were observed for 1 and 2 corresponding to local π–π*-transitions within the dimesitylboryl groups while visible emissions at 541–664 nm with Stokes shifts of 11920–16170 cm−1 were attributed to intramolecular charge transfer transitions between the mesityl and cluster groups. Compound 2 was shown by cyclic voltammetry to form a stable dianion on reduction. NMR spectra for the dianion [2]2− were recorded from solutions generated by reductions of 2 with alkali metals and compared with NMR spectra from reductions of 1,2-diphenyl-ortho-carborane 5. On the basis of observed and computed 11B NMR shifts, these nido-dianions contain bowl-shaped cluster geometries. The carborane is viewed as the electron-acceptor and the mesityl group is the electron-donor in C-dimesitylboryl-1,2-dicarba-closo-dodecaboranes.

Item Type:Article
Full text:(AM) Accepted Manuscript
Download PDF
Full text:(VoR) Version of Record
Available under License - Creative Commons Attribution.
Download PDF
Publisher Web site:
Publisher statement:This article is licensed under a Creative Commons Attribution 3.0 Unported Licence.
Date accepted:24 April 2015
Date deposited:06 May 2015
Date of first online publication:June 2015
Date first made open access:No date available

Save or Share this output

Look up in GoogleScholar