Types Of Donor Groups Research Articles

Towards modulating the colour hues of isoindigo-based electrochromic polymers through variation of thiophene-based donor groups

This paper demonstrated that the hues of both neutral and oxidised colours of isoindigo-based donor–acceptor polymers could be tuned subtly by means of variation of the number and type of donor groups.

Novel hexadentate and pentadentate chelators for 64Cu-based targeted PET imaging

A series of new hexadentate and pentadentate chelators were designed and synthesized as chelators of 64Cu. The new pentadentate and hexadentate chelators contain different types of donor groups and are expected to form neutral complexes with Cu(II). The new chelators were evaluated for complex kinetics and stability with 64Cu. The new chelators instantly bound to 64Cu with high labeling efficiency and maximum specific activity. All 64Cu-radiolabeled complexes in human serum remained intact for 2days. The 64Cu-radiolabeled complexes were further challenged by EDTA in a 100-fold molar excess. Among the 64Cu-radiolabeled complexes evaluated, 64Cu-complex of the new chelator E was well tolerated with a minimal transfer of 64Cu to EDTA. 64Cu-radiolabeled complex of the new chelator E was further evaluated for biodistribution studies using mice and displayed rapid blood clearance and low organ uptake. 64Cu-chelator E produced a favorable in vitro and in vivo complex stability profiles comparable to 64Cu complex of the known hexadentate NOTA chelator. The in vitro and in vivo data highlight strong potential of the new chelator E for targeted PET imaging application.

ChemInform Abstract: Complexes of Phosphorus Halides with Two or More Coordination Bonds

AbstractReview: 106 refs.

Complexes of phosphorus halides with two or more coordination bonds

The review considers complexes of phosphorus as central atom with the variously dentate ligands of different topology and type of donor groups. The most stable complexes form the N-donor ligands, which are strong nucleophiles. The P-donor ligands stabilize the lower oxidation state of phosphorus. Only a few examples of complexes is known of the neutral O- and S-donor ligands. The most stable are the chelates with the ligands forming with the phosphorus atom alongside a donor-acceptor bond also a common covalent bond.

Analysis of sodium, potassium, calcium, and ammonium cation binding and selectivity in one- and two-armed nitrogenpivot lariat ethers

Abstract Complexation of sodium, potassium, calcium, and ammonium cations by one- and two-armed (bibracchial) lariat ethers is surveyed and analyzed. A comprehensive list of binding data determined at 25.0±0.1 °C in anhydrous methanol is presented. More than 100 new, experimentally determined (K s ) and calculated (selectivity) values especially for calcium and ammonium are presented. Both cation binding strength and selectivity are evaluated in terms of ring size, sidearm length, number and type of donor groups and other factors. Hitherto unreported divalent calcium cation binding selectivities for bibracchial lariat ethers in aqueous solution rival the cation selectivities of some cryptands. N,N′-bis(Ethoxycarbonylmethyl)-4,13-diaza-18-crown-6 exhibits a Ca2+/K+ selectivity equal to that of [2.2.1]-cryptand and a Ca2+/Na+ selectivity better than that of any cryptand. Two bibracchial systems having >NCH2CONHCHRCOOCH2CH3 sidearms (R=H, s-butyl), have shown Ca2+ over Na+ selectivity in water of ≥103. Catio...

STRUCTURE-REACTIVITY RELATION FOR THE COMPLEXATION OF Ni, Cd, Zn, AND Fe

Abstract A structure-reactivity relationship is presented which predicts formation constants based solely on the structure of the organic ligand. This relationship has been evaluated using literature values of formation constants for Ni, Cd, Zn, and Fe. In most cases the root-mean-square deviation between observed and calculated log KML values is less than 0.8 log units. The relationship includes an adjustable parameter for each type of donor group coordinated to the metal ion, and the contribution of each donor atom is assumed to be independent of the other ligating groups. A separate term is included to account for the added stability due to the formation of chelate rings.

Chelating agents for metal buffering and analysis in solution

Abstract