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41.
The Donor Properties of Bis(pyrazolyl)‐Sulfur Derivatives From the reactions of bis(pyrazolyl)sulfane S(pz)2 ( 1 ) with the fluoro Lewis acids BF3 and AsF5 in liquid SO2 the 1:2‐adducts S(pz·BF3)2 ( 2 ) and S(pz·AsF5)2 ( 3 ) are obtained. 1 reacts with [Co(SO2)4(FAsF5)2] to give the doubly bridged FAsF4F dimeric complex [Co{S(pz)2}(FAsF5)(SO2)(μ‐FAsF4F)]2 ( 5 ). From F2S(pz)2 and [Ni(SO2)6](AsF6)2, the fluorocubane [Ni4F4{S(pz)2}4(μ‐FAsF4F)2](AsF6)2·4SO2 ( 8 ) is isolated. The X‐ray structures of the compounds 2 , 3 , 5 and 8 are reported. 相似文献
42.
Carsten Knapp Enno Lork Tobias Borrmann Wolf‐Dieter Stohrer Rüdiger Mews 《无机化学与普通化学杂志》2005,631(10):1885-1892
Attempts to prepare t‐BuCN5S3 and the unexpected Isolation of a covalent Modification of Tetrasulfur‐pentanitrogen Chloride S4N5Cl Attempts to prepare the bicyclic sulfur‐nitrogen heterocycle t‐BuCN5S3 via (NSCl)3 and the corresponding silylated amidinates and amidines failed because of the inaccessibility of the silylated intermediates. Reactions of MN(SiMe3)2 (M = Li, Na) with t‐BuCN did not yield the expected amidinates t‐BuC(NSiMe3)2M, instead the adducts [t‐BuCN·MN(SiMe3)2]2 were isolated. The attempted synthesis of t‐BuCN5S3 from t‐BuCN(SiMe3)2M, prepared in situ from t‐BuLi and Me3SiNCNSiMe3, and (NSCl)3 unexpectedly resulted a mixture of S4N5Cl and S5N6. The crystal structure determination for S4N5Cl showed a new covalent modification of S4N5Cl (monoclinic, P21/c, a = 1005.0(4) pm, b = 1193.5(8) pm, c = 1152.5(6) pm, β = 93.67(3)°), different from the known ionic S4N5Cl (orthorhombic, Pnma, a = 1738.90(10) pm, b = 781.50(10) pm, c = 483.03(5)). The unsuccessful attempts to prepare t‐BuCN5S3, the unexpected formation of S4N5Cl and S5N6, and the bonding properties of the new covalent modification of S4N5Cl are discussed. 相似文献
43.
The geometric structure and conformational properties of ((fluoroformyl)imido)(trifluoromethyl)sulfur fluoride, FC(O)N = S(F)CF3, are investigated by gas electron diffraction (GED) experiments, IR (gas) spectroscopy, and quantum chemical calculations (HF, MP2, and B3LYP with 6-31G* basis sets). The GED intensities are reproduced best with a mixture of 79(12)% trans-syn and 21(12)% cis-syn conformers. "Trans/cis" describes the orientation around the S=N double bond (FC(O) group relative to sulfur substituents), and "syn" refers to the orientation of the C=O bond relative to the S=N bond. From the intensities of the C=O bands in the IR (gas) spectrum, a composition of 86(8)%:14(8)% is derived. These ratios correspond to delta G0(GED) = 0.79(36) and delta G0(IR) = 1.09(35) kcal mol-1. The preference of a trans structure, around the S=N double bond is unexpected, since all imidosulfur compounds studied thus far possess a cis configuration. The conformational properties are reproduced qualitatively correctly by all theoretical calculations. The predicted energy differences delta E(HF) = 2.41, delta E(MP2) = 0.64, and delta E(B3LYP) = 0.28 kcal mol-1 are larger or slightly smaller than the experimental values. Additional theoretical calculations (B3LYP) for several imidosulfur compounds reveal that only FC(O)N=S(F)CF3, with mixed substitution at sulfur and the FC(O) group bonded to nitrogen, prefers the trans structure. 相似文献
44.
Reaction of Thiazylfluoride with Multifunctional Nitrogen Derivatives From the reaction of NSF 1 with LiN(SiMe3)R′ (R′ = CMe3, SiMe3), linear [e. g. (Me3C? N?S?N? )2S ( 11 ), Me3C? N?S?N? CMe3 ( 14 ), Me3Si? N?S?N? SiMe3 ( 17 ), (Me3Si)2N? S? N?S?N? SiMe3 ( 19 )] and cyclic thiazenes (S4N5F ( 22 )) are isolated, (S3N4)n ( 23 ) is obtained in high yield from 1 and 17 (in the ratio 2:1). Possible structures for 23 are discussed; the reaction of 23 with AsF5 gives S4N4 · AsF5 ( 24 ) in a hitherto unknown modification. Possible reactions of the terminal SN groups are discussed and the structures of 11 and 24 are reported. 相似文献
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