1,721,393 research outputs found
1,10-phenanthroline: a versatile building block for the construction of ligands for various purposes
No full textThis review will cover the developments in the chemistry of phenanthroline-based ligands in the last
10–15 years. 1,10-Phenanthroline (phen) is a classic ligand in coordination chemistry, which couples versatility
in metal ion binding with peculiar properties of its complexes. For instance, metal complexes with
phenanthroline can be featured by an intense luminescence or can interact with DNA in an intercalative
fashion inducing, in some cases, DNA cleavage. For this reason a number of phenanthroline-containing
ligands has been recently synthesized by inserting phenanthroline within open-chain or macrocyclic
backbone, in order to develop new molecular chemosensors for metal cations and anions, ionophores as
well as new intercalating agents for polynucleotides. Furthermore, phenanthroline is rigid and its insertion
within cyclic or acyclic structures can impart to the resulting ligand a high degree of pre-organization,
affording selective complexing agents. This review will discuss on the coordination, luminescence and
intercalating and/or DNA cleaving properties as well as on analytical applications of metal complexes
with phenanthroline-based ligands. Particular attention will be devoted to macrocyclic receptors or openchain
ligands that, beside the phenanthroline nitrogen atoms, contain other donor atoms able to interact
with the metal cations or anions
Metal-based optical chemosensors for CN− detection
No full textThis critical review focuses on recent advances (2010-2015) in the detection of cyanide anion via metal-based optical chemosensors in which a change in colour and/or fluorescence intensity (or emission wavelength) of a molecular metal complex is determined by the direct interaction of the metal centre with this anio
Halogen-Chalcogen X-E (X = F, Cl, Br, I; E = S, Se, Te) Chemistry: Charge-Transfer (C.-T.) adducts and related compounds
No full textBinding and structural aspects of nitrile- and amino-functionalised pendant arm derivatives of 1,4,7-triazacyclononane ([9]aneN3)
No full text[1-(3-aminopropyl)-4,7-dithia-1-azacyclononane-k4N,N',S,S']bis(dimethylforma mide-kO)nickel(II) bis(tetraphenylborate) acetonitrile disolvate
No full textSynthsis, coordination properties, and analytical applications of mixed-donor macrocycles containing the 1,10-phenanthroline sub-unit
No full textThe coordination properties towards different metal ions of a new class of mixed N/S-, and N/S/O-donor macrocycles
containing the 1,10-phenanthroline sub-unit in the cyclic framework are reviewed. The conformational constraints imposed by the
heteroaromatic fragment onto the aliphatic portion of the ring determine the coordination mode of these ligands which can
stabilise low-valent Ni+, Pd+, Pt+, and Rh+ metal complexes. Structural and thermodynamic aspects of the coordination chemistry
of these ligands are considered together with possible applications as building blocks in the synthesis of multi-centred systems,
and as template in the construction of extended polyiodide networks. However, solution studies demonstrate the inability of these
ligands to work as selective and specific fluorescent chemosensors for heavy transition and post-transition metal ions and the
formation constants evaluated for the formation of 1:1 complexes with Pb2+, Cd2+, Hg2+, Cu2+, and Ag+ in acetonitrile are of the
same order of magnitude. Nevertheless, some of these macrocyles are extremely effective to recognise Cu2+ or Ag+ over the other
metal ions in transport processes, and have been successfully used as neutral ionophore in the construction of PVC-based ionselective
electrodes and supported liquid membranes for analytical detection and separation, respectively, of these metal ions
A new pyridine-based 12-membered macrocycle functionalised with different fluorescent subunits: optical response to CuII, ZnII, CdII, HgII and PbII
No full textSensing and activation of anionic species by polyamine-based metal complexes
No full textThe role of metal complexes with polyamine ligands in selective binding of anions and their possible use
as optical chemosensors or biologically relevant hydrolytic agents for anionic substrates will be discussed
on the basis of some study cases from the work of the authors, with particular emphasis on the cooperative
action of metal cation and polyamine receptor in both the processes of interaction and sensing/
activation
A supported liquid membrane system for simultaneous separation of silver(I) and mercury(II) from dilute feed solutions
No full textAn innovative application of supported liquid membranes (SLMs) to the selective simultaneous separation of Ag+ and Hg2+ ions from a dilute
feed by employing a two-membrane–three-compartment cell is introduced. Two micro-porous PP supported membrane loaded with a mixed
N/O/S-donor macrocycle aza-thioether crown containing the 1,10-phenanthroline sub-unit (PhenS2O) and tetrathia-12-crown-4 (TT12C4) were
used for selective transport of silver and mercury ions, respectively. The PhenS2O-loaded membrane was placed between the first and the second
compartments, whereas the TT12C4-loaded membrane was placed between the second and the third compartments of the transport cell. The use of
this cell assembly, under optimized experimental conditions, made it possible to transport Ag+ and Hg2+ ions simultaneously from a 1.0×10−3M
picric acid feed solution containing these two species and several other interfering ions into the two corresponding strip compartments of the
transport cell. Sodium thiosulfate (0.04 M) and EDTA disodium salt (0.025 M) were used as stripping agents for Ag+ and Hg2+ ions, respectively
- …
