Darstellung, 11 B-NMR- und Schwingungsspektren von cis-Dinitrotetrahydro-closo-hexaborat(2–), cis-[B6H4( NO2)2]2- sowie Kristallstruktur von cis-Cs2[B6H4(NO2)2] / Preparation, 11 B NMR and Vibrational Spectra of cis-Dinitrotetrahydro-closo-hexaborate(2–),cis-[B6H4(NO2)2]2-, and the Crystal Structure of cis-Cs2[B6H4(NO2)2

Abstract

By electrochemical oxidation of [B6H6,]2 in the presence of nitrite ions and of the base DBU in dichloromethane solution apart from [B6H5 (NO2)]2- and [B6H5(NO)B 6H5]3- the dinitro anion cis-[B6H4( NO2)2]2- is formed and can be isolated by ion exchange chromatography on diethylaminoethyl cellulose. The crystal structure of the Cs salt has been determined from single crystal X-ray diffraction analyses. cis-Cs2[B6H4 ( NO2)2] is tetragonal, space group P4̄21 m with a = 10.0656(4), c = 11.0127(13) Å. The 11B NMR spectrum is consistent with a disubstituted octahedral B6 cage with local C2v symmetry. The IR and Raman spectra exhibit characteristic NO2, B - H and B6 vibrations.