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51.
35Cl NQR spectra of dichlorophosphates Me(PO2Cl2)2 · 2D (Me = Mg, Ca, Mn; D = CH3COOC2H5, CH3COCH3, POCl3) are studied in the temperature range 77 ? T (K) ? 305. It is shown that the three compounds with CH3COOC2H5 as donor are isomorphic at 77 K, the crystal structure of Mn(PO2Cl2)2· 2CH3COOC2H5. The structure of Mg(PO2Cl2)2?· 2CH3COCH3 and of Mg(PO2Cl2)2 · 2POCl3 probably consists of infinite chains as found for Mn(PO2Cl2)2· 2CH3COOC2H5. Mg(PO2Cl2)2· 2CH3COOC2H5 shows phase transformations and a complicated dynamical behaviour leading to strong deviations from a Bayertype NQR function v = f(T). The donor capacity of POCl3 in Mg(PO2Cl2)2· 2POCl3 is comparable with the donor strength in AsCl3 · POCl3 · A dπ-pπ overlap of the P-O bond influences the P-Cl bond. 相似文献
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Gáti T Simon A Tóth G Magiera D Moeller S Duddeck H 《Magnetic resonance in chemistry : MRC》2004,42(7):600-604
Adducts of four phosphine chalcogenides with the chiral dirhodium complex ([Rh-Rh]) were investigated by variable-temperature 1H and 31P NMR spectroscopy in order to compare their properties as axial ligands. Whereas the selenide (1) and the sulfide (2) are strong ligands with electrostatic attraction and, in addition, a significant orbital (HOMO-LUMO) interaction, the phosphine oxide compounds (P=O) bind primarily via electrostatic attraction and are relatively weak donors. Moreover, the overall bond strength in these adducts depends on steric congestion around the P=O group. 相似文献
53.
Hydroxylamido(1-)-O,N Complexes of Molybdenum(VI) Containing Terminal Oxo, Sulfido, and Selenido Ligands. Crystal Structures of [MoO2(C5H10NO)2] and of [MoS2(C5H10NO)2] Molecular complexes of cis-dioxo-bis(hydroxylamido(1-)-O,N)molybdenum(VI) containing O,N-coordinated, N,N-substituted hydroxylamine ligands react with H2S in toluene substituting one or both terminal oxo groups yielding cis-oxosulfido- and cis-disulfido-bis (hydroxylamido(1-)-O,N) molybdenum complexes, respectively. With H2Se the corresponding cis-oxoselenido complexes are formed. The crystal structures of the two title compounds containing piperidine-N-oxide as ligands are described: The cis-disulfido complex crystallizes tetragonal in the space group D—I 4 2 m with four formula units per unit cell; the corresponding cis-dioxo complex crystallizes orthorhombic (D—P 212121; Z = 4). The 1H—nmr spectra and the UV-visible absorption spectra are reported. 相似文献
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Helmut Sprdizer Andrea Pichler Wolfgang Holzer Irene Toth Bettina Zuchart 《Helvetica chimica acta》1997,80(1):139-145
Khusimone (1), one of the main odor-donating compounds of vetiver oil is subject of the following study on structure/odor relationship. The omittance of the ethano bridge of the tricyclic khusimone leads to a bicyclic system. The stereoselective approach to this degraded structure is described, and the olfactory properties are studied. The key step of the synthesis of the hydrindane nucleus is based on a highly diastereoselective conjugate addition to a chiral oxo-cyclopentene-2-carboxylate. 相似文献
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By investigation of isomeric 2H- and 13C-labelled C9H11 Cl-compounds it has been shown that the ion [M ? Cl]+ is transformed mainly to the ion [C7H7]+ via C2H4-elimination from alkyl-substituted tropylium-ions. Phenyl-cyclopropane-cations play only a small part, if at all, in this fragmentation process. 相似文献
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