Preparation, B-11 NMR, vibrational spectra and crystal structure of [P(C6H5)(4)](2)[1,10-(O2N)(2)B10H8]

By reaction of [N(C4H9)(4)](2)[B10H10] in aqueous acetonitrile with NO2 a reaction mixture is formed from which -[1,10-(O2N)(2)B10H8](2-) has been isolated by ion exchange chromatography on diethylaminoethyl(DEAE) cellulose. The X-ray structure determination of [P(C6H5)(4)](2)[1,10-(O2N)(2)B10H8] (triclinic, space group P (1) over bar, a = 10.83(3), b = 13.059(3), c = 18.496(5) Angstrom, alpha = 82.13(2), beta = 75.87(2), gamma = 71.08(2)degrees, Z = 2) reveals the coordination of both nitro groups via N in the apical positions of the B-10 cluster with B1-N1 = 1.526(3) and B-10-N-2 = 1.537(3) Angstrom and ONO angles of 119.3(2) and 120.1(2)degrees. The B-11 NMR spectrum exhibits the characteristic feature (2:8) of a in 1,10 position disubstituted B-10 cluster with a strong downfield shift of the ipso-B atoms at +17.3 ppm. The IR and Raman spectra show strong NO stretching vibrations at 1384 and 1425 cm(-1).