Preparation, B-11, C-13 NMR and vibrational spectra of Cs-2[B6H5(p-C6H4(NO2))], Cs-2[B6H5 (C6H3-1-(CH3)-5-(NO2))] and crystal structure of (CH2Py2)[B6Cl5(p-C6H4(NO2))] center dot CH3CN

The first aryl derivatives of closo-hexahydrohexaborate are formed by react ion of [B6H6](2-) with 1-bromo-4-nitrobenzene and 2-bromo-5-nitrotoluene in acetonitrile at 80 degreesC. Cs-2[B6H5-(1,4-C6H4(NO2))] and Cs-2[B6H5(C6H3 -1-(CH3)-5-(NO2))] can be isolated by ion exchange chromatography on diethy laminoethyl (DEAE) cellulose. Further treatment with N-chlorosuccinimide yi elds the perhalogenated derivative (CH2Py2)[B6Cl5(1,4-Ph(NO2))]. CH3CN whic h has been characterized by X-ray diffraction analysis (orthorhombic, space group P2(1)2(1)2(1), a = 9.810(4), b = 14.412(3), c = 18.586(9) Angstrom, Z = 4). The B-11 NMR spectra of all compounds are consistent with a monosub stituted B-6-cluster. The IR and Raman spectra exhibit characteristic BE, B H, CH, CC and NO vibrations, respectively.