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14-,18-, and 22-membered tetraaza macrocycles have been prepared by the reaction of acetylacetone with ethylenediamine, 1,4-butanediamine, or 1,6-hexanediamine, respectively. Their copper(II) and nickel(II) complexes were characterized by electronic and infrared spectroscopies. The 14-membered macrocycle forms a mononuclear copper(II) complex with a planar structure, whereas the 18-membered macrocycle forms a mononuclear copper(II) complex with a pseudo-tetrahedral structure, and the 22-membered macrocycle forms di- and trinuclear copper(II) complexes. The complexation and extraction abilities of these macrocycles toward copper(II) and nickel(II) ions are discussed.

Some chloromanganese(III) Schiff base complexes react with hydrogen chloride to give deep green complexes with the empirical formula of MnLCl2 or MnL′2Cl2, where H2L denotes quadridentate ligands such as N,N′-disalicylideneethylenediamine and its analogs, and where HL′ denotes bidentate ligands such as N-butylsalicylideneamine and its analogs. These complexes are nonelectrolytes in acetonitrile. Their magnetic moments at room temperature fall within the range of 3.9 to 4.1 BM, and the magnetic susceptibilities obey the Curie-Weiss law with small θ values over the temperature range of 77 to 300 K, indicating that the oxidation state of the manganese ions in these complexes is +IV. The electronic spectra show an intense band around 16000 cm−1 which can be assigned to a charge-transfer transition. In the cyclic voltammograms, two cathodic waves are observed at half-peak potentials around +0.9 V and −0.2 V(vs. SCE); they can be assigned to the reductions of Mn(IV) to Mn(III) and of Mn(III) to Mn(II) respectiv...

A series of monomeric chloroiron(III) complexes with the quadridentate or quinquedentate Schiff bases such as N,N′-disalicylideneethylenediamine or bis[3-(salicylideneamino)propyl]amine react with superoxide ions, O2−, in dimethyl sulfoxide to give the corresponding μ-oxo dimers. The polymeric chloroiron(III) complexes with the polymeric (oligomeric) Schiff bases derived from 5,5′-methylenedisalicylaldehyde and triamines react with O2− in dimethyl sulfoxide to give the oxygenated complexes, probably dioxygen adducts, FeIII–O2−. This is suggested by the absorption spectra and the polarographic measurements.

The chlorobis(N-alkylsalicylideneaminato)manganese(III) complexes, MnIII(N-Rsai)2Cl, react with hydrogen chloride to give the corresponding dichloromanganese(IV) complexes, MnIV(N-Rsai)2Cl2, as deep green crystals; R can be n-C3H7, n-C4H9, i-C4H9, n-C6H13, c-C6H11, n-C8H17, n-C12H25, n-C18H37, CH2C6H5, or CH2CH2C6H5. These complexes were characterized by the magnetic susceptibilities, electronic spectra, infrared spectra, and cyclic voltammograms. The complexes (R=n-C12H25 and n-C18H37) are found to be stable toward water in the solid state. A trans, six-coordinate configuration is proposed for these Mn(IV) complexes on the basis of the infrared spectra.

The reactions of the chloromanganese(III) complexes of the Schiff bases derived from salicylaldehydes or β-diketones and diamines or monoamines with superoxide ion, O2−, in dimethyl sulfoxide were investigated. The complexes were found to react to give either the oxygenated Mn Schiff base complexes or the reduced Mn(II) Schiff base complexes. The difference in the reactivity toward O2− was correlated to the polarographic half-wave potentials corresponding to the reduction of Mn(III) to Mn(II) of the complexes. Some oxygenated complexes were isolated and characterized.

By the reaction of MnII(salen) (salen=N,N′-ethylenebis(salicylideneiminato) dianion) and its analogues with molecular oxygen in organic solvents, three types of complexes including as structural units the MnIII–O2–MnIII,–(–MnIV–O–)–n, and MnIV=O bonds respectively, have been obtained, and characterized by means of their electronic and infrared spectra, by thermogravimetric analysis, and in terms of their magnetic properties. The lower magnetic moments for [MnIII(salen)]2O2 and –[–MnIV(salen)–O–]–n than those expected have been interpreted in terms of antiferromagnetic interactions. The oxo complex was found to give the catena-oxo complex quantitatively in a DMF, DMSO, or Py solution. The effects of the oxygen partial pressure and the nature of the substituent in the organic part on the complex formation were investigated. A lower partial pressure of oxygen has the advantage of yielding the μ-peroxo complex in a higher yield. A discussion of the reaction mechanism is also included.

The polymeric Mn(III) Schiff base complexes react with superoxide ions (O2−) in dimethyl sulfoxide (DMSO) to give the oxygenated complexes, while the corresponding monomeric Mn(III) complexes are reduced with O2− to the Mn(II) complexes.