Darstellung, 11B-NMR- und Schwingungsspektren von μ-Distickstoff-bis(pentahydro-closo-hexaborat)(2-), [B6H5(NN)B6H5]2-sowie Kristallstruktur von [As(C6H5)4]2[B6H5(NN)B6H5] / Preparation, 11B NMR and Vibrational Spectra of μ-Dinitrogen-bis(pentahydro-closo-hexaborate)(2-), [B6H5(NN)B6H5]2 and the Crystal Structure of [As(C6H5)4]2[B6H5(NN)B6H5]

Abstract

Abstract By reduction of [B6H5(NO2)]2- with aluminium powder in aqueous alkaline solution the orange μ-dinitrogen-bis(pentahydro-closo-hexaborate)(2-), [B6H5(NN)B6H5]2-, is formed, which can be precipitated with tetraphenylarsonium ions. The crystal structure of [As(C6H5)4]2[B6H5(NN)B6H5] has been determined by single crystal X-ray diffraction analy­sis; tetragonal, space group P4/n with a = 12.6610(12), c = 14.6790(11) Å. The B6 cages are slightly compressed (2%) in the direction of the connecting linear N2 bridge with bond lengths N-N of 1.129 and B-N of 1.421 Å. The 11B NMR spectrum exhibits signals at -27.0 (ipso-B), +1.26 (equatorial-B), +3.54 ppm (antipodal-B atoms). The NN stretching vibration is observed in the Raman spectra as a very strong line at 2065 cm-1.