Potentiometric and spectroscopic studies of the copper(II) complexes with some aminodiphosphonic acids in aqueous solution

The complexing properties of oxalodihydrazide, acethydrazide and formic hydrazide with Cu(II) in aqueous solution

“…2, sim 1) for the complex with Ah and A || = 160 Â 10 À4 cm À1 , g || = 2.334 with Fh, respectively. These parameters are consistent with the presence of an NO3 donor set in an xy Cu(II) ion plane from one ligand chelating through amine and oxygen donors and two oxygens from water molecules [45,50].…”

“…The short distances between the donor groups cause an increase of mutual electronic effects following an increase in the acidities and a decrease in pK values [44]. The difference of pK for Ah and Fh is consistent with the electronic effects of the substituents attached to the carbonyl group [45]. The greater electrodonating potential of the methyl group than the hydrogen atom increases the electron density on the oxygen and nitrogen atoms, thus resulting in a more basic increase of pK for the donor groups of Ah.…”

“…hence log 10 K CuL 2 H CuL 2 H 2 ¼ log 10 b 122 À log 10 b 121 ¼ 30:79 À 25:25 ¼ 5:54 and pK CuL 2 H 2 CuL 2 H ¼ 5:54 is considerably lower than the corresponding deprotonation constant of the free ligand for the amide proton (pK 1 = 11.86, Table 1), as noted in reference [45].…”

Highly stable acyclic bifunctional chelator for 64Cu PET imaging

“…Interestingly, these thermodynamic data point out the high stability of the copper(II) complexes formed with L 1 , comparable to those Table 3). These monometallic Cu(II) complexes are also much more stable than the L A model [59][60][61], which represents a subunit of L 1 , and than L G [48], the carboxylate analogue of L 1 (Chart 2).…”

“…The most attractive production routes of 64 Cu are: proton irradiation of highly enriched 64 Ni [6,7], which produces only minor short lived 61 Co impurities, and deuteron bombardment of nat Zn [8], for which the main impurities concerned isotopes of 55−58 Co, 57,65 Ni(II), 65,69m Zn(II) and 66,67 Ga(III). A good candidate for 64 Cu chelation should thus ideally be able to discriminate Cu(II) in a mixture containing all these cations.…”