1870-69-5Relevant articles and documents
Synthesis and X-ray structures of amidinate, oxoamidate, and thioamidate complexes of boron
Blais, Pierre,Chivers, Tristram,Downard, Andrew,Parvez, Masood
, p. 10 - 15 (2000)
The reactions of PhBCl2 with Li[CE(N'Bu)((n)Bu)] or Li[CS(N'Bu)(NH'Bu)] (1:1 molar ratio) in toluene at 23°C produced the heterocycles Ph(Cl)B(μ-N'Bu)(μ-E)C((n)Bu) (1a, E = N'Bu; 1b, E = O; 1c, E = S) or Ph(Cl)B(μ-N'Bu)(μ-S)C(NH'Bu) (2), which were characterized by 1H, 11B and 13C NMR and by mass spectra. X-ray structural determinations revealed that 1a, 1c and 2 contain four-membered rings. In 2 the thioamidate ligand adopts an N,S bonding mode. Crystal data: 1a, monoclinic, space group P21, a = 8.816(3), b = 11.311(2), c = 10.168(3) A, β = 98.86(3)°, V = 1001.7(5) A3, Z = 2, R = 0.042, and R(w) = 0.020; 1c, monoclinic, space group P21/n, a = 7.617(2) b = 11.200(1), c = 19.568(2), β = 90.74(2)°, V = 1669.1(5) A3, Z = 4, R = 0.046, and R(w) = 0.059; 2, monoclinic, space group P21/a, a = 11.357(2), b = 12.289(2), c = 12.620(3) A, β = 95.43(2)°, V = 1753.4(5) A3, Z = 4, R = 0.043, and R(w) = 0.027.
Electronic Structure and Bonding in Cyclic B-S and B-Se Compounds Studied by Solid State 11B NMR
Conrady-Pigorsch, R.,Mueller-Warmuth, W.,Schwetlik, G.,Wienkenhoever, M.,Krebs, B.
, p. 453 - 458 (2007/10/02)
Solid state 11B (and in one case 10B) NMR spectra of four cyclic boron-chalcogen compounds have been measured at various frequencies and analysed in terms of nuclear quadrupole and chemical shift interactions.Application of the Townes-Dailey theory to the quadrupole results, corrected for ionic contributions to the electric field gradient and to the bonding, yields detailed information about the importance of ?-bonding in the respective materials.The occupation number of the 2pz orbitals of the sp2-hybridized boron atoms appear to be particularly large for systems containing chalcogen-chalcogen bridges.From both the chemical point of view and the spectroscopic result, among the six- and five-membered rings, diiodotriselenadiborolane is distinguished by an exceptional position.
