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

Kahlert, J; Böhling, L; Brockhinke, A; Stammler, HG; Neumann, B; Rendina, LM; Low, PJ; Weber, L; Fox, MA

HERO ID

2902151

Reference Type

Journal Article

Year

2015

Language

English

PMID

25939355

HERO ID 2902151
In Press No
Year 2015
Title Syntheses and reductions of C-dimesitylboryl-1,2-dicarba-closo-dodecaboranes
Authors Kahlert, J; Böhling, L; Brockhinke, A; Stammler, HG; Neumann, B; Rendina, LM; Low, PJ; Weber, L; Fox, MA
Journal Dalton Transactions (Online)
Volume 44
Issue 21
Page Numbers 9766-9781
Abstract Two C-dimesitylboryl-1,2-dicarba-closo-dodecaboranes, 1-(BMes2)-2-R-1,2-C2B10H10 (, R = H, , 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 and are hydrolysed on prolonged exposure to air to give mesitylene and boronic acids 1-(B(OH)2)-2-R-1,2-C2B10H10 (, R = H, , R = Ph respectively). Addition of fluoride anions to and resulted in boryl-carborane bond cleavage to give dimesitylborinic acid HOBMes2. UV absorption bands at 318-333 nm were observed for and corresponding to local π-π*-transitions within the dimesitylboryl groups while visible emissions at 541-664 nm with Stokes shifts of 11 920-16 170 cm(-1) were attributed to intramolecular charge transfer transitions between the mesityl and cluster groups. Compound was shown by cyclic voltammetry to form a stable dianion on reduction. NMR spectra for the dianion [](2-) were recorded from solutions generated by reductions of with alkali metals and compared with NMR spectra from reductions of 1,2-diphenyl-ortho-carborane . On the basis of observed and computed (11)B 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.
Doi 10.1039/c5dt00758e
Pmid 25939355
Wosid WOS:000355000700008
Is Certified Translation No
Dupe Override No
Is Public Yes
Language Text English