کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
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1335718 | 979546 | 2006 | 8 صفحه PDF | دانلود رایگان |
![عکس صفحه اول مقاله: Phosphoamide – modified p-tert-butyl calix[4]arene and its sodium complexes: Synthesis, coordination ability and structure Phosphoamide – modified p-tert-butyl calix[4]arene and its sodium complexes: Synthesis, coordination ability and structure](/preview/png/1335718.png)
A new modified calix[4]arene, namely 5,11,17,23-tetra-tert-butyl-25,27-dihydroxy-26,28-bis[(tetramethyldiamidophosphinyl)oxy]calix[4]arene (L) has been prepared by reacting the parent calixarene with tetramethyldiamidophosphoric acid chloride, and its structure was solved by the X-ray diffraction method in the solid state and characterized in solution using 1H, 13C, 31P NMR and mass spectral (ES-MS and FAB-MS) data. The coordination ability of L towards Na+ showed the formation of two different complex species, [NaL]+[AuCl4]− · 4H2O (1) and [Na2L2](ClO4)2 · (CH3OH)4 (2), depending on the reaction conditions and nature of the counter ion. Complex 1 is structurally characterized using NMR (1H, 13C, 31P) and mass spectral data. Complex 2 crystallizes with four molecules of methanol, two of them being bridges between two calixarene units and its structure was determined by X-ray analysis.
The X-ray structure of the complex [Na2L2](ClO4)2 · 4CH3OH comprises of 2 calix[4]arene ligands, 2Na+, 2(ClO4)− and 4CH3OH. Each of the calix[4]arene ligands participate in the complex, being bonded to Na+ by only one of the PO groups. Both Na+ cations are placed outside of the ligand cavities. Each cation is coordinated to one ClO4- (Na+ is directly bonded to one oxygen of the perchlorate), one terminal and two bridging CH3OH molecules.Figure optionsDownload as PowerPoint slide
Journal: Polyhedron - Volume 25, Issue 11, 31 July 2006, Pages 2261–2268