Serious concerns about the negative impact of ethylenediaminetetraacetic acid (EDTA) on the environment resulted in severe restrictions imposed on this compound in many countries. One of the main concerns is related to the use of EDTA in agriculture as a chelator in microelement fertilizers: being introduced directly into the sawing fields, it penetrates into groundwater, with no chance to be captured/recycled. Respectively, there is an active search for environmentally friendly, biodegradable alternatives for this chelator.
View Article and Find Full Text PDFThe reduction of -nitrophenol to -aminophenol has become a benchmark reaction for testing the efficiency of new catalytic systems. In this study, we use oxidatively modified carbon (OMC) as a structural support to develop a new cost-efficient nickel-based catalytic system. The newly developed material comprises single nickel ions, chemically bound to the oxygen functional groups on the OMC surface.
View Article and Find Full Text PDFA family of three- and four-coordinated silver(I) complexes of formulas [Ag(PPh ) L], [Ag(PPh )L], and [AgL] with N-thiophosphorylated thiourea and thioamide ligands of general formula RC(S)NHP(S)(OPri) [R = Ph, PhNH, iPrNH, tBuNH, NH ] have been studied by solid-state Ag and P CPMAS NMR spectroscopy. Ag NMR spectra have provided valuable structural information about Ag coordination, which is in good accordance with the available crystal structure data. The data presented in this work represent a significant addition to the available Ag chemical shifts and chemical shifts anisotropies.
View Article and Find Full Text PDFReaction of the potassium salts of N-thiophosphorylated thioureas of common formula RC(S)NHP(S)(OiPr)(2) [R = morpholin-N-yl (HL(a)), piperidin-N-yl (HL(b)), NH(2) (HL(c)), PhCH(2)NH (HL(d))] with Cu(PPh(3))(3)I in aqueous EtOH/CH(2)Cl(2) leads to mononuclear [Cu(PPh(3))(2)L-S,S'] complexes. Using copper(i) iodide instead of Cu(PPh(3))(3)I, polynuclear complexes [Cu(n)(L-S,S')(n)] were obtained. The structures of these compounds were investigated by ES-MS, elemental analyses, 1H and 31P NMR in solution, IR and 31P solid-state MAS NMR spectroscopy.
View Article and Find Full Text PDFOctamethoxy calix[8]arenes substituted in the para position by amide, urea, and imide functions were synthesized from the octamethyl ether of tert-butylcalix[8]arene by ipso nitration, reduction, and acylation. Scanning force microscopy of spin coated samples on graphite suggests that these derivatives self-organize into tubular nanorods via hydrogen bonds between p-amide functions. A single-crystal X-ray structure reveals a centrosymmetric conformation for the octanitro derivative.
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