Selective Extraction and Transport of the [PtCl<sub>6</sub>]<sup>2−</sup>Anion through Outer-Sphere Coordination Chemistry
作者:Rebecca J. Warr、Arjan N. Westra、Katherine J. Bell、Jy Chartres、Ross Ellis、Christine Tong、Timothy G. Simmance、Anastasia Gadzhieva、Alexander J. Blake、Peter A. Tasker、Martin Schröder
DOI:10.1002/chem.200802377
日期:2009.5.4
recovery: Tripodal receptors incorporating urea, amido or sulfonamido hydrogen‐bond donors show high loading and selectivity for extraction of [PtCl6]2− over chloride (present in 60‐fold excess) from a low pH aqueous phase to organic media (see figure). The formation of neutral 2:1 [LH]+/[PtCl6]2− packages in organic solvents is supported by single‐crystal X‐ray structure determinations.
Anion complexation of a pentafluorophenyl-substituted tripodal urea receptor in solution and the solid state: selectivity toward phosphate
作者:I. Ravikumar、P. S. Lakshminarayanan、M. Arunachalam、E. Suresh、Pradyut Ghosh
DOI:10.1039/b820322a
日期:——
literature shows anionbinding with this receptor in solution. Solution state binding studies of L(1) are carried out by (1)H-NMR titration to calculate binding constants, which show the following anionbinding sequence H(2)PO(4)(-) > SO(4)(2-)> CH(3)COO(-) > F(-) > Cl(-) >> Br(-) whereas there is no binding with I(-), NO(3)(-) and ClO(4)(-) guests. Comparison of phosphate and sulfatebinding in L(1) and
Tris(2-aminoethyl)amine and cis-1,3,5-tris(aminomethyl)cyclohexane have been checked as spacers for phosphate receptors. Ureas are better binding arms than thioureas for these spacers while the combination of this first functional group with chromenone fragments permits further increases in the phosphate and sulfate association constants.