Takayuki Matsushita

Preparation and characterization of a novel macrocyclic ligand—dinitro-tetraazacyclotetradeca-tetraene—and application as a highly selective extractant for copper(II)

A novel tetraaza macrocyclic Schiff base ligand, 6,13-dinitro-5,7,12,14-tetramethyl-1,4,8,11-tetraazacyclotetradeca-1,5,7,-12-tetraene, was prepared and its copper(II) and nickel(II) complexes were characterized. This ligand was found to be an excellent extractant for copper(II).

Reaction of dichloromanganese(IV) Schiff-base complexes with water as a model for water oxidation in photosystem II

Abstract The dichloromanganese(IV) Schiff-base complexes Mn(N-R-3-NO2 sal)2Cl2 (R = n-C3H7, n-C4H9, n-C6H13,

Ion-pair extraction of the gallium(III) ion from hydrochloric acid with various methoxy-substituted triarylphosphines

Abstract A series of methoxy-substituted triarylphosphines RnPh3-nP (n = 1−3), where R may be 2-(MeO)C6H4,4-(MeO)C6H4,2,6-(MeO)2C6H3 and 2,4,6-(MeO)3C6H2, have been prepared and employed as extractants for the gallium(III) ion from hydrochloric acid solutions. The extractabilities of these compounds are found to become more effective with an increase in their basicities, which are determined by non-aqueous titrimetry. Highly basic compounds, {(2,6-(MeO)2C6H3)}3P and {(2,4,6-(MeO)3C6H2)}3P, possess the highest extractability amongst the triarylphosphines. The extraction mechanism is discussed on the basis of the 1H and 31P NMR spectroscopic data.

Preparation and characterization of dichlorobis(N-alkyl-substituted salicylideneaminato)manganese(IV) complexes

Abstract A series of dichlorobis(N-alkyl-substituted salicylideneaminato)manganese(IV) complexes, Mn(N-R-Xsal) 2 Cl 2 , was prepared by the reaction of Mn(NRXsal) 2 Cl complexes with hydrogen chloride, where R can be n -C 8 H 17 (Oct), n -C 12 H 25 (Dod), n -C 18 H 37 (Octd), and CH 2 C 6 H 5 (Bz) and X can be 5-bromo, 5-nitro, and 5,6-benzo groups. These complexes were characterized by the magnetic susceptibilities, IR and electronic spectra, and cyclic voltammograms.

Preparation of a novel polymeric ligand containing a tetraaza macrocycle supported on polystyrene, and separation of copper(II) and nickel(II)

Abstract The novel polymeric ligand containing the tetraaza macrocycle as a pendant group was prepared by the reaction of 2,7,12,14-tetramethyl-1,4,8,11-tetraazacyclotetradeca-1,5,7,12-tetraene with iodomethylstyrene-divinylbenzene copolymer beads. The content of the ligand in the polymer was 0.75 mmol g −1 under the optimum conditions. The complexation of this polymer with copper(II) and nickel(II) in water under heterogeneous conditions in a batch system showed that it can bind copper(II) selectively by complex formation with the tetraaza macrocycle. The capacity for copper(II) was found to depend on the pH, ionic strength and ethanol content of the sample solutions. Moreover, the separation of nickel(II) and copper(II) was achieved in a column system.

A facile synthesis of unsymmetrical tetradentate schiff-base ligands and their copper(II) and nickel(II) complexes

Abstract A facile synthetic route for unsymmetrical tetradentate Schiff-base ligands has been found by using 5-carboxysalicylaldehyde as a starting material, and their copper(II) and nickel(II) complexes have been prepared and characterized by magnetic susceptibilities, electronic absorption spectra, and polarographic reduction potentials.

Synthesis of polymeric ligands having a tetraaza macrocycle selective for copper(II)

Abstract The novel polymeric ligands, poly-(N 4 )H 2 ( I ) and poly-(N 4 )H 2 ( II ), in which the tetraaza macrocycle was present as an integral

Synergic effects of poly(vinylbenzyltriphenylphosphoniumchloride) on the spectrophotometric determination of lanthanum, aluminum and beryllium

Abstract Poly(vinylbenzyltriphenylphosphonium chloride) reacts more strongly with acidic dyes than quaternary ammonium salts such as zephiramine. This polymer can be used to improve the spectrophotometric determinations of lanthanum, aluminum, and beryllium when it is added to the binary La–xylenol orange, Al–pyrocatechol violet and Be–chromazurol S systems. The molar absorptivities for these systems are similar to those obtained with quaternary ammonium salts, but there are advantages of greater stability and lower reagent consumption.

Preparation of novel polymer ligands containing tetraaza macrocyclic Schiff base as a highly selective extractant for copper(II)

Abstract Three types of the novel polymer ligands in which 6,8,15,17-tetramethyl-dibenzo-5,9,14,18-tetraaza-cyclotetradecene (L) is present as an integral part of the polymer backbone have been prepared. These polymer ligands are oligomers whose polymerization degree may be about five. Their complexing abilities and extractabilities for copper(II) and nickel(II) have been investigated. Among the polymer ligands, Poly-L3, which contains triethyleneglycol bis( p -phenylene) group as a linkage group, was found to be an excellent extractant for copper(II).

Preparation and characterization of copper(II) and nickel(II) complexes with novel tetraaza-macrocyclic schiff bases

Abstract Novel tetraaza-macrocycles with N-substituted carbamoyl groups were prepared by the reaction of 5,7,12,14-tetramethyl-1,4,8,11-tetraazacyclotetradeca-1,5,7,12-tetraene with isocyanates (RNCO, R = Ch3 and C6H5). Their copper(II) and nickel(II) complexes were characterized by magnetic susceptibilities, electronic absorption spectra, and electrochemical properties. The complexing abilities and extractabilities of the ligands for the metal ions were investigated.