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1.
2.
合成了Nd(ClO_4)_3·4phP=O·C_2H_5OH配合物,用四园衍射仪测定了它的分子及晶体结构,此晶体属三斜晶系P1空间群,晶胞参数为:a=13.475(61)A;b=15.003(15)A;c=18.697(15)A;α=85.44(7);β=78.49(24)°;γ=83.13(26)°;V=3671.2A,分子由99个非氢原子组成,实际上分子可分为三个部分即:配阳离子[Nd(ClO_4)_2·4phPO]~+;阴离子ClO_4和溶剂合分子C_2H_5OH配阳离子的钕与八个氧配位,四个氧来自双齿配位的ClO_4,四个氧来自四个ph_3PO,八个配位氧组成三角十二面体。 中性膦(磷)类化合物包括(RO)_3P=O和R_3P=O是一类重要的萃取剂。工业上已应用的TBP和TOPO都属于这一类。为了研究这类萃取剂在不同底液中萃取行为之所以不同的内在因素,我们制备了不同希土盐类与三苯基氧膦的配合物,并对它们进行了结构测定。已知的中性氧膦希土配合物中进行过结构测定的有Ce(NO)·2phP=O、Nd(NO)_2·2php=O·C_2HOH、La(NO_3)_3·3php=O·C_2H_5OH·CHCl_3和Nd(NCS)·4php=O。这些配合物晶体及分子结构各异,这表明了三苯基氧膦在形成配合物时的复杂性。本文报导的Nd(ClO_4)·4phP=O·C_2H_5OH实际上是由三部分组成;即[Nd(ClO_4)_2·4phP=O]~+外界的ClO_4和溶剂合分子。这在中性配体与高氯酸希土形成的配合物中时有发现。已知结构的 相似文献
3.
Ovakimyan M. Zh. Barsegyan S. K. Karapetyan A. A. Panosyan G. A. Indzhikyan M. G. 《Russian Chemical Bulletin》2002,51(9):1744-1747
The reactions of phenylhydrazine and hydroxylamine with (-X-ethyl)triphenylphosphonium salts (X = Ph, Ph3P+Br–) (1, 2) afforded the corresponding -N-ethyl-substituted triphenylphosphonium salts (3, 4). The reaction of triphenyl(2-phenylhydrazinoethyl)phosphonium bromide 3with an aqueous solution of NaOH in benzene afforded a statistical mixture of the nisand transisomers of 2-(diphenylphosphoryl)acetaldehyde phenylhydrazone. (2-Hydroxyaminoethyl)triphenylphosphonium bromide reacted with sodium methoxide to give O-phosphobetaine. 相似文献
4.
Maria De Fenza Anna Esposito Daniele DAlonzo Annalisa Guaragna 《Molecules (Basel, Switzerland)》2021,26(6)
The de novo synthesis of piperidine nucleosides from our homologating agent 5,6-dihydro-1,4-dithiin is herein reported. The structure and conformation of nucleosides were conceived to faithfully resemble the well-known nucleoside drugs Immucillins H and A in their bioactive conformation. NMR analysis of the synthesized compounds confirmed that they adopt an iminosugar conformation bearing the nucleobases and the hydroxyl groups in the appropriate orientation. 相似文献
5.
Farahnaz Nourmohammadian Mahnaz Davoudzadeh Gholami 《Phosphorus, sulfur, and silicon and the related elements》2013,188(2):340-346
A convenient and efficient, regioselective, solvent-free procedure has been developed to react 2,6-dihydroxyanthraquinone, dialkyl acetylenedicarboxylates, and triphenylphosphine in one-pot, to afford novel phosphanylidene anthracenyl derivatives 3a-c, which at 90°C due to intramolecular nucleophilic attack formed novel phosphanylidene anthra[2,1-b]furans 4a–c in good yield. 相似文献
6.
《Green Chemistry Letters and Reviews》2013,6(3):403-407
Abstract The synthesis of diamino triphenyl methanes from aniline and aromatic aldehydes was conducted in near critical water and supercritical water. The reaction parameters, such as temperature, density, and reaction time, have been studied. Significant acceleration of the condensation reaction of aniline and aromatic aldehydes can be achieved by using high temperature water, especially near the critical point, in the absence of any acid catalysts. It has been demonstrated that high temperature water act effectively in the place of conventional acid catalysts. 相似文献
7.
Lawrence C. Thompson Kyle S. Knight William T. Pennington 《Journal of chemical crystallography》2003,33(5-6):403-407
A triphenyl analog of taddol, 4-R,5-R-[5-(hydroxy-diphenyl-methyl)-2,2-dimethyl-[1,3]dioxolan-4-yl]-phenyl-methanone, has been synthesized and structurally characterized. This molecule could act as a chiral ligand building block in the creation of tuned taddol analogs. Structural analysis of the title compound reveals that the hydroxyl group is involved in an intramolecular hydrogen bond and does not take part in any intermolecular interaction. Crystal packing is influenced by C–H O hydrogen bonding and phenyl phenyl interactions. Crystal data: Triclinic, P1 (No. 1), a = 5.9343(4) Å, b = 8.2367(17) Å, c = 10.987(2) Å, = 88.290(6), = 75.442(4), = 80.655(6), V = 512.86(15) Å3, Z = 1, D
calc = 1.258 mg/m3. Final residual values were R
1 = 0.0407 for 3022 observed data (I > 2s(I) ) and wR
2 = 0.0941 for all 3524 unique data. 相似文献
8.
9.
Issa Yavari Maryam Sabbaghan Zinatossadat Hossaini Majid Ghazanfarpour‐Darjani 《Helvetica chimica acta》2008,91(6):1144-1147
Triphenyl phosphite reacts smoothly with dialkyl acetylenedicarboxylates and hexachloroacetone to produce alkyl 2‐(dichloromethylene)‐2,5‐dihydro‐5‐oxo‐4‐(trichloromethyl)furan‐3‐carboxylates in good yields. 相似文献
10.
Ali Ramazani Morteza Rouhani Aram Rezaei Nahid Shajari Ali Souldozi 《Helvetica chimica acta》2011,94(2):282-288
Reactions of biacetyl (=butane‐2,3‐dione) with (N‐isocyanimino)triphenylphosphorane in the presence of aromatic carboxylic acids proceed smoothly at room temperature and under neutral conditions to afford 3‐(5‐aryl‐1,3,4‐oxadiazol‐2‐yl)‐3‐hydroxybutan‐2‐one derivatives in high yields. 相似文献