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1.
Extraction of 3d-Metal Ions by Bidendate Sulfonamides. I. Ligands with Sulfur or Heterocyclic Nitrogen as a Second Donor Atom The properties of 2-acetylpyridine-p-toluensulfonylhydrazone (APSH - H), arensulfonylthioureas (I), and the esters of arensulfonylmonothiocarbamic acid (II) or arensulfonyldithiocarbamic acid (III) as extractants for the late 3d-metal ions are proved. APSH-H is comparable to the proprietary extractant LIX 34. But, because of the special structure of the corresponding 1,2-chelates, the pH1/2-values of nickel(II) and cobalt(II) are ≈2 units lower. The pKs-values, measured in dioxane-water mixtures (75 per cent v/v), increase in the order III < II < I. In aqueous solutions compounds of type III are acids of medium strength. In the case of compounds of type I the substituents of the non-sulfonated nitrogen have a strong influence on the pKs-values (ΔpKs = 4.6). Among the late 3d-elements, the ligands II and III extract only copper(II) (pH1/2 ~2.7 or ~1.6), the ligands I extract zinc(II), cobalt(II), and nickel(II) as well, but not iron(II) and iron(III). The reasons of this unique behaviour are discussed. 相似文献
2.
(Extraction of alkali on alkaline earth metal ions with (sym-dibenzo-14-crown-4-oxy)- and (sym-dibenzo-16-crown-5-oxy)-carboxylic acids.)The extraction of lithium, sodium, potassium, calcium and some other metal ions with dibenzo-4-crown-4-oxy- and dibenzo-16-crown-5-oxycarboxylic acids containing the groups -CH2COOH, -(CH2)2COOH, -(CH2)3COOH, -CH(C2H5)COOH and -CH(C4H9)COOH was studied. The extraction increases as a function of the lipophilic character of the carboxylic acid group. Calcium, barium and strontium ions are better extracted than Li+, Na+ and K+; there are only small differences among the alkaline earth metal ions. Evaluated from the extraction data, the composition of the extracted species was 1:1 (metal/ligand) for Li+, and 1:2 for CaCa2+; Na+ and K+ favour the formation of 1:2 complexes with dibenzo-14-crown-4-derivatives bbut 1:1 complexes with dibenzo-16-crown-5-oxy-carboxylic acids. The dependence of the distribution ratio on pH does not provide unequivocal evidence for the composition of the extracted compounds. 相似文献
3.
Kathrin Wichmann Bianca Antonioli Tilo Shnel Marco Wenzel Kerstin Gloe Karsten Gloe Jason R. Price Leonard F. Lindoy Alexander J. Blake Martin Schrder 《Coordination chemistry reviews》2006,250(23-24):2987
In the discussion that follows some of the more recent progress in the area of anion binding by synthetic polyamine receptors is presented, with emphasis given to work undertaken by the authors’ groups. A continuing theme in these studies has been the relationship between receptor structure and its anion extraction properties.Systematic solvent extraction and structural studies for halide and perrhenate complexes with polyamines of tripodal, macrocyclic and macrobicyclic architecture that contain both aromatic moieties and four to eight amine functions have been performed in order to derive relevant structure-binding/extractability relationships. The results demonstrate that the binding and extraction behaviour of the polyamines towards halides and perrhenate is a complex function of their structural features, degree of protonation and lipophilic properties. The extraction is characterized by the preferred formation of mono- and diprotonated amine species in the organic phase. X-ray structure studies of iodide and perrhenate complexes with open-chain tetraamino derivatives and octaamino cryptands in different protonation states lead to the conclusion that in the first case only limited chelation of the anion occurs and in the second only highly protonated species are able to encapsulate the anion. The structural patterns observed are strongly influenced by the presence of water molecules in the crystals. 相似文献
4.
Silvia Stumpf Gudrun Goretzki Kerstin Gloe Karsten Gloe Wilhelm Seichte Edwin Weber Jan W. Bats 《Journal of inclusion phenomena and macrocyclic chemistry》2003,45(3-4):225-233
The di- and tetra-allyl ethers of tert-butylcalix[4]arene 1 and 2 have been prepared by alkylation of tert-butylcalix[4]arene with allyl bromide and K2CO3 using different reaction times. Solution 1H NMR measurement of the di-allyl ether 1 and X-ray crystal structures of the complexes of 1 with chloroform (1a) or methanol (1b) indicate the cone conformation of 1 in which intramolecular hydrogen bonding can be maximized. The crystalline state conformers 1a and 1b are distorted in different grades depending on the solvent. While methanol is incorporated in the macrocycle, chloroform molecules do not occupy the cage. The solution 1H NMR spectra of tetra-allyl ether 2 show the co-existence of the cone and partial cone conformation. The partial cone conformer of 2 was investigated by X-ray crystallography. In this compound hydrogen bonding is not existent. The conformer distribution is likely affected by steric and template effects. 相似文献
5.
Olaf Heitzsch Karsten Gloe Alfréd Sabela Jiří Koryta Edwin Weber 《Journal of inclusion phenomena and macrocyclic chemistry》1992,13(4):311-319
The complex forming properties with alkali metal and ammonium ions of a series of oligo benzo-condensed 18-crown-6 ethers1–8 having a different gradation of lipophilicity and of molecular rigidity are investigated by voltammetry at the interface of two immiscible electrolyte solutions (ITIES) and by a liquid-liquid extraction technique. The experimental results obtained in the two phase system H2O/nitrobenzene are discussed in relation to the structure of the crown and the cation type. The stability constants for the 1 : 1 complexes of Na+, K+, Rb+, Cs+ and NH
4
+
in nitrobenzene have been determined and compared with the extraction constants for the 1: 1 complexes of Na+ and K+ and for the 1 : 1 and 1 : 2 complexes of Cs+, showing the effect of oligo benzo condensation for the 18-crown-6 system. 相似文献
6.
Polymeric melaminium sulfate [(LH2)2(SO4)2]n has been synthesized by reaction of melamine L with sulfuric acid in aqueous solution. The compound was characterized by elemental analysis, 1H NMR, ESI MS and a single crystal X‐ray diffraction analysis. The architecture of the assembly formed is based on hydrogen bonded dimers of diprotonated melaminium cations (LH2)2+ which are linked by a hydrogen bonded network with sulfate ions forming 2D sheets. A 3D polymeric structure results from the presence of mutual hydrogen bonds between sulfate ions and melaminium cations in different sheets. Significant π‐π stacking is also present between the aromatic cations in this supramolecular arrangement. 相似文献
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8.
Linda GötzkeKerstin Gloe Katrina A. JolliffeLeonard F. Lindoy Axel HeineThomas Doert Anne JägerKarsten Gloe 《Polyhedron》2011,30(5):708-714
The interaction of di(2-picolyl)amine (1) and its secondary N-substituted derivatives, N-(4-pyridylmethyl)-di(2-picolyl)amine (2), N-(4-carboxymethyl-benzyl)-di(2-picolyl)amine (3), N-(4-carboxybenzyl)-di(2-picolyl)amine (4), N-(1-naphthylmethyl)-di(2-picolyl)amine (5), N-(9-anthracenylmethyl)-di(2-picolyl)amine (6), 1,4-bis[di(2-picolyl)aminomethyl]benzene (7), 1,3-bis[di(2-picolyl)aminomethyl]benzene (8) and 2,4,6-tris[di(2-picolyl)amino]triazine (9) with Ni(II) and/or Zn(II) nitrate has resulted in the isolation of [Ni(1)(NO3)2], [Ni(2)(NO3)2], [Ni(3)(NO3)2], [Ni(4)(NO3)2]·CH3CN, [Ni(5)(NO3)2], [Ni(6)(NO3)2], [Ni2(7)(NO3)4], [Ni2(8)(NO3)4], [Ni3(9)(NO3)6]·3H2O, [Zn(3)(NO3)2]·0.5CH3OH, [Zn(5)(NO3)2], [Zn(6)(NO3)2], [Zn(8)(NO3)2] and [Zn2(9)(NO3)4]·0.5H2O. X-ray structures of [Ni(4)(NO3)2]·CH3CN, [Ni(6)(NO3)2] and [Zn(5)(NO3)2] have been obtained. Both nickel complexes exhibit related distorted octahedral coordination geometries in which 4 and 6 are tridentate and bound meridionally via their respective N3-donor sets, with the remaining coordination positions in each complex occupied by a monodentate and a bidentate nitrato ligand. For [Ni(4)(NO3)2]·CH3CN, intramolecular hydrogen bond interactions are present between the carboxylic OH group on one complex and the oxygen of a monodentate nitrate on an adjacent complex such that the complexes are linked in chains which are in turn crosslinked by intermolecular offset π-π stacking between pyridyl rings in adjacent chains. In the case of [Ni(6)(NO3)2], two weak CH?O hydrogen bonds are present between the axial methylene hydrogen atoms on one complex and the oxygen of a monodentate nitrate ligand on a second unit such that four hydrogen bonds link pairs of complexes; in addition, an extensive series of π-π stacking interactions link individual complex units throughout the crystal lattice. The X-ray structure of [Zn(5)(NO3)2] shows that the metal centre once again has a distorted six-coordinated geometry, with the N3-donor set of N-(1-naphthylmethyl)-di(2-picolyl)amine (5) coordinating in a meridional fashion and the remaining coordination positions occupied by a monodentate and a bidentate nitrato ligand. The crystal lattice is stabilized by weak intermolecular interactions between oxygens on the bound nitrato ligands and aromatic CH hydrogens on adjacent complexes; intermolecular π-π stacking between aromatic rings is also present. 相似文献
9.
A novel convenient synthetic route for poly-functional 21-monothiatetraphenylporphyrins of the type A4 und AB3 having base labile substituents in meso position was developed. Using this method a series of symmetric and asymmetric 21-thiaporphyrins containing different functional groups at the meso position is reported. The new products were characterized by NMR, UV-Vis and mass spectroscopy. 相似文献
10.
The extraction behaviour of acylthioacetamides, R1—CO—CH2—CS—NR2R3, was studied for a series of transition metals. The highest distribution ratios were obtained with benzoylthioacetanilide. Complexes with acylthioacetamides which were completely substituted on the amide group were extracted slowly. The ranking of the extraction characteristics is related to the different pKa values of the compounds used. Polymerization and solvation reactions can be excluded at metal concentrations of ? 10-3 mol dm-3 and extractant concentrations of ?10-1 mol dm-3, respectively. Decreasing extractability, Cu(II) > Zn(II) > Ni(II) > Co(II) > Cd(II), corresponds to the stability constants of the extracted metal chelates. Iron(III) cannot be extracted at pH ?3; Hg(II), Pd(II), and Au(III) are extracted readily over a reasonably wide pH range. The different extraction constants for zinc(II) and cadmium(II) permit an effective separation of these ions with benzoylthioacetanilide. 相似文献