Ferric ion immobilized on three-dimensional nanoporous gold films modified with self-assembled monolayers for electrochemical detection of hydrogen peroxide

A fast, simple square wave potential method is developed for the fabrication of a three-dimensional (3D) nanoporous gold (NPG) film. The nanostructures are characterized and confirmed by scanning electronic microscopy (SEM) and cyclic voltammetry (CV). The nanostructures modified with self-assembled monolayers (SAMs) are employed as an electrode substrate to immobilize inorganic iron(III) ion. After immobilization, iron(III) ion undergoes an effective direct electron transfer reaction with a pair of well-defined redox peak at -256 ± 10 mV (pH 7.0). The iron(III) ion modified electrode displays the excellent electrocatalytic performance for reduction of hydrogen peroxide, and thus can be used as an electrochemical sensor for detecting hydrogen peroxide with a low detection limit (1.0 × 10(-9) M), a wide linear range (9.0 × 10(-7)~5.0 × 10(-4) M), as well as good stability, selectivity and reproducibility.     

Influence of solvent and counter ion on complexes of 2,5-bis(2-pyridyl)-1,3,4-oxadiazole with iron (II) and (III) studied by electrospray ionization mass spectrometry

The effect of solvent and counter ion on the complexes of 2,5-bis(2-pyridyl)-1,3,4-oxadiazole (1) with Fe+2 and Fe+3 has been studied by electrospray ionization mass spectrometry (ESI/MS). As expected, upon ESI conditions the metal reduction proceeds, but it can be deduced that complexes with Fe+2 are favored over those with Fe+3. When methanol is used as solvent, the formation of complexes of stoichiometry 2:1 and 1:1 with counter ion attached (monovalent anion) is favored, for example, [1(2)+FeCl]+ ion. The use of methanol/water (1/1) as solvent favors the formation of complexes of stoichiometry 2:1 and 3:1, namely doubly charged [1(2)+Fe]+2 and [1(3)+Fe]+2 ions. The complexes containing anion of oxidative properties (ClO4-, NO3-), when the higher cone voltage is applied, yield unusual species [1n+FeOm]+ (n=1, 2; m=1, 2). The use of divalent counter ion (SO4(-2)) resulted in formation of complexes containing two iron cations, namely [1n+Fe2SO4]+2 (n=2, 3, 4) ions. These ions can be regarded as Fe-1 complexes bridged by a sulfate anion.     

Kinetics and mechanism of the oxidation of iron(II) ion by chlorine dioxide in aqueous solution

The mechanism by which an excess of iron(II) ion reacts with aqueous chlorine dioxide to produce iron(III) ion and chloride ion has been determined. The reaction proceeds via the formation of chlorite ion, which in turn reacts with additional iron(II) to produce the observed products. The first step of the process, the reduction of chlorine dioxide to chlorite ion, is fast compared to the subsequent reduction of chlorite by iron(II). The overall stoichiometry is The rate is independent of pH over the range from 3.5 to 7.5, but the reaction is assisted by the presence of acetate ion. Thus the rate law is given by At an ionic strength of 2.0 M and at 25°C, k_u = (3.9 ± 0.1) × 10³ L mol^?1 s^?1 and k_c = (6 ± 1) × 10⁴ L mol^?1 s^?1. The formation constant for the acetatoiron(II) complex, K_f, at an ionic strength of 2.0 M and 25°C was found to be (4.8 ± 0.8) × 10^?2 L mol^?1. The activation parameters for the reaction were determined and compared to those for iron(II) ion reacting directly with chlorite ion. At 0.1 M ionic strength, the activation parameters for the two reactions were found to be identical within experimental error. The values of ΔH? and ΔS? are 64 ± 3 kJ mol^?1 and + 40 ± 10 J K^?1 mol^?1 respectively. © 2004 Wiley Periodicals, Inc. Int J Chem Kinet 36: 554–565, 2004     

Sequential determination of iron(II) and iron(III) in pharmaceutical by flow-injection analysis with spectrophotometric detection.

A flow injection procedure for the sequential spectrophotometric determination of iron(II) and iron(III) in pharmaceutical products is described. The method is based on the catalytic effect of iron(II) on the oxidation of iodide by bromate at pH = 4.0. The reaction was monitored spectrophotometrically by measuring the absorbance of produced triiodide ion at 352 nm. The activating effect for the catalysis of iron(II) was extremely exhibited in the presence of oxalate ions, while oxalate acted as a masking agent for iron(III). The iron(III) in a sample solution could be determined by passing through a Cd-Hg reductor column introduced in the FIA system to reduce iron(III) to iron(II), which allows total iron determination. Under the optimum conditions, iron(II) and iron(III) could be determined over the range of 0.05 - 5.0 and 0.10 - 5.0 microg ml(-1), respectively with a sampling rate of 17 +/- 5 h(-1). The experimental limits of detection were 0.03 and 0.04 microg ml(-1) for iron(II) and iron(III), respectively. The proposed method was successfully applied to the speciation of iron in pharmaceutical products.     

Simultaneous determination of copper and iron by second derivative spectrophotometry using mixtures of ligands

A highly sensitive and selective second derivative spectrophotometric method has been developed for the determination of copper and iron in mixtures. The method is based on the separation of the analytes by liquid-liquid extraction as picrate ion pairs. Iron-picrate, reacts in the organic phase of DCE with 5-phenyl-3-(4-phenyl-2-pyridinyl)-1,2,4-triazine (PPT). Similarly the copper-picrate reacts with 2,9-dimethyl-4,7-diphenyl-1,10-phenantroline (bathocuproine). The extracts were evaluated directly by derivative spectrophotometric measurement, using the zero-crossing approach for determination of copper and graphic method for iron. Iron and copper were thus determined in the ranges 8-120 ng ml(-1) and 8-125 ng ml(-1), respectively, in the presence of one another. The detection limits achieved (3sigma) were 2.9 ng ml(-1) of iron and 2.8 ng ml(-1) of copper. The relative standard deviations were in all instances less than 2.1%. The proposed method was applied to the determination of both analytes in river and tap water and the results were consistent with those provided by the AAS standard method.     

Preconcentration of iron (III), cobalt (II) and copper (II) nitroso-R complexes on tetradecyldimethylbenzylammonium iodide-naphthalene adsorbent

Iron, cobalt and copper form coloured water soluble anionic complexes with disodium 1-nitroso-2-naphthol-3-6-disulphonate (nitroso R-salt). The anionic complex is retained quantitatively as a water insoluble neutral ion associated complex (M-nitroso R-TDBA) on tetradecyldimethylbenzylammonium iodide on naphthalene (TDBA(+)I(-)-naphthalene) packed column in the pH range of: Fe(III): 3.1-6.5, Co: 3.4-8.5 and Cu 5.9-8.0 when their solutions are passed individually over this adsorbent at a flow rate of 0.5-5.0 ml/min. The solid mass consisting of an ion associated metal complex along with naphthalene is dissolved out of the column with 5 ml dimethylformamide/chloroform and metals are determined spectrophotometrically. The absorbance is measured at 710 nm for iron, 425 nm for cobalt and 480 nm for copper. Beers law is obeyed in the concentration range 9.2-82 mug of iron, 425 nm for cobalt cobalt and 3.0-62 mug of copper in 5 ml of final DMF/CHCl(3) solution. The molar absorptivities are calculated to be Fe: 7.58 x 10(3), Co: 1.33 x 10(4) and Cu: 4.92 x 10(4)M(-1)cm(-1). Ten replicate determinations containing 25 mug of iron, 9.96 mug of cobalt and 3.17 mug of copper gave mean absorbances 0.677, 0.450 and 0.490 with relative standard deviations of 0.88, 0.98 and 0.92%, respectively. The interference of large number of metals and anions on the estimations of these metals has been studied. The optimized conditions so developed have been employed for the trace determination of these metals in standard alloys, waste water and fly ash samples.     

A near-infrared spectroscopic study of the phosphate mineral pyromorphite Pb5(PO4)3Cl

Spectral properties as a function composition are analysed for a series of selected pyromorphite minerals of Australian origin. The minerals are characterised by d-d transitions in NIR from 12,000 to 8000 cm(-1) (0.83-1.25 microm). A broad signal observed at approximately 10,000cm(-1) (1.00 microm) is the result of ferrous ion impurity in pyromorphites and follows a relationship between band intensity in the near-infrared spectra and ferrous ion concentration. The iron impurity causes a change in colour from green-yellow to brown in the pyromorphite samples. The observation of overtones of the OH(-) fundamentals, confirms the presence OH(-) in the mineral structure. The contribution of water-OH overtones in the NIR at 5100 cm(-1) (1.96 microm) is an indication of bonded water in the minerals of pyromorphite. Spectra in the mid-IR show that pyromorphite is a known mixed phosphate and arsenate complex, Pb5(PO4,AsO4)3Cl. A series of bands are resolved in the infrared spectrum of pyromorphite at 1017, 961 and 894 cm(-1). The first two bands are assigned to nu(3), the antisymmetric stretching mode and the third band at 894 cm(-1) is the symmetric mode of the phosphate ion. Similar patterns are shown by other pyromorphite samples with variation in intensity. The cause of multiple bands near 800 cm(-1) is the result of isomorphic substitution of (PO4)(3-) by (AsO4)(3-) and the spectral pattern relates to the chemical variability in pyromorphite. The presence of (AsO4)(3-) is significant in certain pyromorphite samples.     

Solvent sublation and spectrometric determination of iron(II) and total iron using 3-(2-pyridyl)-5,6-bis(4-phenylsulfonic acid)-1,2,4-triazine and tetrabutylammonium bromide.

Solvent sublation has been studied for the separation and determination of trace iron(II) in various kinds of water samples. A strongly magenta-colored anionic [Fe(FZ)3](4-) complex was formed at pH 5.0 upon adding 3-(2-pyridyl)-5,6-bis(4-phenylsulfonic acid)-1,2,4-triazine (ferrozine, FZ) to the sample solution. Tetrabutylammonium bromide (TBAB) was added in the solution to form the (TBA)4[Fe(FZ)3)] ion pair, and an oleic acid (HOL) surfactant was added. Then, the (TBA)4[Fe(FZ)3] ion pairs were floated by vigorous shaking in the flotation cell and extracted into methyl isobutyl ketone (MIBK) on the surface of the aqueous solution. The iron collected in the MIBK layer was measured directly by spectrophotometry and/or flame atomic-absorption spectrophotometry. Different experimental variables that may affect the sublation efficiency were thoroughly investigated. The molar absorptivity of the (TBA)4[Fe(FZ)3] ion pair was 2.8 x 10(4) l mol(-1) cm(-1) in the aqueous layer. Beer's law held up to 1.0 mg L(-1) Fe(II) in the aqueous as well as in the organic layers. The adopted solvent sublation method was successfully applied for the determination of Fe(II) in natural water samples with a preconcentration factor of 200. The application was extended to determine iron in pharmaceutical samples.     

Mononuclear, dinuclear, and pentanuclear [[N,S(thiolate)]iron(II)] complexes: nuclearity control, incorporation of hydroxide bridging ligands, and magnetic behavior

The mixed N3S(thiolate) ligand 1-[bis[2-(pyridin-2-yl)ethyl]amino]-2-methylpropane-2-thiol (Py2SH) was used in the synthesis of four iron(II) complexes: [(Py2S)FeCl] (1), [(Py2S)FeBr] (2), [(Py2S)4Fe5II(mu-OH)2](BF4)4 (3), and [(Py2S)2Fe2II(mu-OH)]BF4 (4). The X-ray structures of 1 and 2 revealed monomeric iron(II)-alkylthiolate complexes with distorted trigonal-bipyramidal geometries. The paramagnetic 1H NMR spectra of 1 and 2 display resonances from delta = -25 ppm to +100 ppm, consistent with a high-spin iron(II) ion (S = 2). Spectral assignments were made on the basis of chemical shift information and T1 measurements and show the monomeric structures are intact in solution. To provide entry into hydroxide-containing complexes, a novel synthetic method was developed involving strict aprotic conditions and limiting amounts of H2O. Reaction of Py2SH with NaH and Fe(BF4)2.6 H2O under aprotic conditions led to the isolation of the pentanuclear, mu-OH complex 3, which has a novel dimer-of-dimers type structure connected by a central iron atom. Conductivity data on 3 show this structure is retained in CH2Cl2. Rational modification of the ligand-to-metal ratio allows control over the nuclearity of the product, yielding the dinuclear complex 4. The X-ray structure of 4 reveals an unprecedented face-sharing, biooctahedral complex with an [S2O] bridging arrangement. The magnetic properties of 3 and 4 in the range 1.9-300 K were successfully modeled. Dinuclear 4 is antiferromagnetically coupled [J = -18.8(2) cm(-1)]. Pentanuclear 3 exhibits ferrimagnetic behavior, with a high-spin ground state of S(T) = 6, and was best modeled with three different exchange parameters [J = -15.3(2), J' = -24.7(3), and J' = -5.36(7) cm(-1)]. DFT calculations provided good support for the interpretation of the magnetic properties.     

The coextraction of rhenium with pyridylazonaphtholates of indium,iron(III) and thallium(III)

The extraction of indium, iron(III) and thallium(III) complexes with 1-(2-pyridylazo)-2-naphthol is enhanced by the presence of perrhenate ion. Rhenium is coextracted with these metals in the form of ion associates of the InA₂⁺ReO₄^- type. where A is the anion 1-(2-pyridylazo)-2-naphthol.     

Liquid chromatographic determination of cobalt(II), copper(II) and iron(II) using 2-thiophenaldehyde-4-phenyl-3-thiosemicarbazone as derivatizing reagent

The complexing reagent 2-thiophenaldehyde-4-phenyl-3-thiosemicarbazone (TAPT) was examined for high performance liquid chromatographic (HPLC) separations of cobalt(II), copper(II) and iron(II) or cobalt(II), nickel(II), iron(II), copper(II) and mercury(II) as metal chelates on a Microsorb C-18, 5-mum column (150x4.6 mm i.d.) (Rainin Instruments Woburn, MA, USA). The complexes were eluted isocratically with methanol:acetonitrile:water containing sodium acetate and tetrabutyl ammonium bromide (TBA). UV detection was at 254 nm. The solvent extraction procedure was developed for simultaneous determination of the metals, with detection limits within 0.5-2.5 mug ml(-1) in the final solution. The method was applied for the determination of copper, cobalt and iron in pharmaceutical preparation.     

芳基吡啶类Fe3+荧光探针的合成与分析应用

设计合成了两种新型的以2-苯基苯并噻唑为荧光团、N-(2-吡啶甲基)胺为识别基团的铁离子荧光分子探针2-(4-N-2-吡啶甲胺基)苯基-1,3-苯并噻唑(A1)和2-(4-N,N双2-吡啶甲胺基)苯基-1,3-苯并噻唑(A2),化合物结构用UV,IR,1HNMR和13CNMR进行了表征,并考察了探针的荧光特性.结果表明荧光分子探针A2在CH3 CH2OH/H-12O(1∶1,V/V)溶液中,能从常见的金属离子中以95％的荧光淬灭率选择性地识别铁离子,对Fe3+线性响应范围在0.15～1.3 μ mol/L之间,且检出限达10 nmol/L.     

Selection of the counter-cation in the solvent extraction of anionic chelates: Spectrophotometric determination of trace amounts of cobalt with 2-nitroso-1-naphthol-4-sulphonic acid and tetrabutylammonium ion

The importance of selecting the most suitable counter-cation in the solvent extraction-spectrophotometric determination of an anionic metal chelate containing a sulphonic acid group is demonstrated and discussed. In the case of cobalt and 2-nitroso-1-naphthol-4-sulphonic acid (nitroso-NW acid), the most suitable counter-cation is the tetrabutylammonium ion (Bu(4)N(+)): in this case only the ion-pair of the anionic cobalt chelate is extracted into chloroform and the excess of the nitroso-NW acid remains in the aqueous phase. The absorption maximum of the chelate in chloroform is at 307nm, at which the molar absorptivity is 6.5 x 10(4)l.mole(-1).cm(-1). The absorbance of the reagent blank at 307 nm is less than 0.010. By use of nitroso-NW acid and Bu(4)N(+), trace amounts of cobalt may be determined in nickel salts and in iron and steel samples.     

2:2 Fe(III):ligand and "adamantane core" 4:2 Fe(III):ligand (hydr)oxo complexes of an acyclic ditopic ligand

A bis-hydroxo-bridged diiron(III) complex and a bis-mu-oxo-bis-mu-hydroxo-bridged tetrairon(III) complex are isolated from the reaction of 2,6-bis((N,N'-bis-(2-picolyl)amino)methyl)-4-tert-butylphenol (Hbpbp) with iron perchlorate in acidic and neutral solutions respectively. The X-ray structure of the dinuclear complex [{(Hbpbp)Fe([mu-OH)}(2)](ClO(4))(4).2C(3)H(6)O (1.2C3H6O) shows that only one of the metal-binding cavities of each ligand is occupied by an iron(III) atom and two [Fe(Hbpbp)]3+ units are linked together by two hydroxo bridging groups to form a [Fe(III)-(mu-OH)](2) rhomb structure with Fe...Fe = 3.109(1)A. The non-coordinated tertiary amine of Hbpbp is protonated. Magnetic susceptibility measurements show a well-behaved weak antiferromagnetic coupling between the two Fe(III) atoms, J= -8 cm(-1). The tetranuclear complex [(bpbp)(2)Fe(4)(mu-O)(2)(mu-OH)(2)](ClO(4))(4)(2) was isolated as two different solvates .4CH(3)OH and .6H(2)O with markedly different crystal morphologies at pH ca. 6. Complex .4CH(3)OH forms red cubic crystals and .6H(2)O forms green crystalline platelets. The Fe(4)O(6) core of shows an adamantane-like structure: The six bridging oxygen atoms are provided by the two phenolato groups of the two bpbp(-) ligands, two bridging oxo groups and two bridging hydroxo groups. The hydroxo and oxo ligands could be distinguished on the basis of Fe-O bond lengths of the two different octahedral iron sites: Fe-mu-OH, 1.953(5), 2.013(5)A and Fe-mu-O, 1.803(5), 1.802(5)A. The difference in ligand environment is too small for allowing Mossbauer spectroscopy to distinguish between the two crystallographically independent Fe sites. The best fit to the magnetic susceptibility of .4CH(3)OH was achieved by using three coupling constants J(Fe-OPh-Fe)= 2.6 cm(-1), J(Fe-OH-Fe)=-0.9 cm(-1), J(Fe-O-Fe)=-101 cm(-1) and iron(III) single ion ZFS (|D|= 0.15 cm(-1)).     

Mono- and binuclear complexes of iron(II) and iron(III) with an N4O ligand: synthesis, structures and catalytic properties in alkane oxidation

Three mononuclear iron complexes and one binuclear iron complex, [Fe(tpoen)Cl].0.5(Fe2OCl6) (1), [Fe(tpoen)Cl]PF6 (2), Fe(tpoen)Cl3 (3) and [[Fe(tpoen)]2(mu-O)](ClO4)4 (4) (tpoen = N-(2-pyridylmethoxyethyl)-N,N-bis(2-pyridylmethyl)amine), were synthesized as functional models of non-heme iron oxygenases. Crystallographic studies revealed that the Fe(II) center of 1 is in a pseudooctahedral environment with a pentadentate N4O ligand and a chloride ion trans to the oxygen atom. The Fe(III) center of 3 is ligated by three nitrogen atoms of tpoen and three chloride ions in a facial configuration. Each Fe(III) center of 4 is coordinated with four nitrogen atoms and an oxygen atom of tpoen with the Fe-O-Fe angle of 172.0(3) angstroms. Complexes 2, 3 and 4 catalysed the oxidation of cyclohexane with H2O2 in the total TNs of 24-36 with A/K ratios of 1.9-2.4. Under the same conditions they also catalysed both the oxidation of ethylbenzene to benzylic alcohol and acetobenzene with good activity (30-47 TN) and low selectivity (A/K 0.7), and the oxidation of adamantane with moderate activity (15-18 TN) and low regioselectivity (3 degrees/2 degrees 3.0-3.2). With mCPBA as oxidant the catalytic activities of 2, 3 and 4 increased 1.8 to 2.3-fold for the oxidation of cyclohexane and ethylbenzene and 6.3 to 7.5-fold for the oxidation of adamantane. Drastic enhancement of the regioselectivity was observed in the oxidation of adamantane (3 degrees/2 degrees 18.5-30.3).     

Redox reaction of artemisinin with ferrous and ferric ions in aqueous buffer.

Artemisinin, a sesquiterpene with endoperoxide bond, possesses potent antimalarial activity against the ring and late stage of chloroqine-resistant Plasmodium falciparum malaria both in vitro and in vivo. The mode of antimalarial activity of artemisinin is iron-dependent. The aim of this study was to investigate the reactions of artemisinin with ferrous and ferric ions in aqueous buffer. Artemisinin generated a cycle of iron oxidation and reduction. It oxidized ferrous and reduced ferric ions with similar rate of reaction (k=10+/-0.5 M(-1) x s(-1) for ferrous and k=8.5+/-2.0 M(-1) x s(-1) for ferric ion). The major active product was dihydroartemisinin which exhibited antimalarial activity at least 3 times more potent than artemisinin. Dihydroartemisinin preferably binds to ferric ion, forming ferric-dihydroartemisinin complex. The re-oxidation of the complex gives artemisinin and ferric ion. This suggests that in aqueous buffer, the reaction of artemisinin with iron may give rise to the active reaction products, one of them being dihydroartemisinin, which is responsible for antimalarial activity.     

Synthesis and structure of [Fe(13)O(4)F(24)(OMe)(12)](5-): the first open-shell Keggin ion

The reaction between ferric fluoride trihydrate and pyridine in hot methanol produced yellow-brown crystals of (PyH)5.[Fe13O4F24(OMe)12].4H2O.CH3OH. The anionic complex [Fe13O4F24(OMe)12]5- (1), which has a full Td symmetry, is the first example of an open-shell Keggin ion consisting of 13 high-spin d5 iron(III) atoms. The central, tetrahedral {FeO4} unit in 1 is surrounded by 12 octahedral iron atoms, which are bridged by methoxide oxygen atoms and fluoride ligands. In addition, each of the 12 iron atoms is coordinated to a terminal fluoride ligand with an Fe-F distance of 1.846(3) A. Magnetic susceptibility studies indicate strong exchange interactions between the iron atoms, the mueff value of 19.3 muB at 300 K being significantly lower than that expected for thirteen uncoupled S = 5/2 centers.     

Iron salts with the tetracyanidoborate anion: [Fe(III)(H2O)6][B(CN)4]3, coordination polymer [Fe(II)(H2O)2{κ2N[B(CN)4]}2], and [Fe(II)(DMF)6][B(CN)4]2

The reaction of Fe(OH)(3) with tetracyanidoboronic acid, H[B(CN)(4)]·xH(2)O, in water leads to the first examples of tetracyanidoborates with a triply charged metal cation, [Fe(III)(H(2)O)(6)][B(CN)(4)](3) (1). Using elemental iron powder as starting material, [Fe(II)(H(2)O)(2){κ(2)ΝB(CN)(4)]}(2)] (2) is obtained. Anhydrous iron(II) tetracyanidoborate, which is synthesized by heating of 2, is soluble in dry dimethylformamide. After evaporation of the DMF solvent, single crystals of the third title compound, [Fe(II)(DMF)(6)][B(CN)(4)](2) (3), are obtained. Compound 3 is the first metal tetracyanidoborate soluble in nonpolar solvents. The title compounds have been characterized by single-crystal X-ray diffraction (1 rhombohedral, R3c (no. 167), a = 14.9017(7) ?, c = 20.486(1) ?, Z = 6; 2 tetragonal, I42d (no. 122), a = 12.3662(3) ?, c = 9.2066(4) ?, Z = 4; 3 triclinic, P1 (no. 2), a = 8.6255(3) ?, b = 11.0544(4) ?, c = 12.2377(5) ?, Z = 1). The metal ions in all three compounds are octahedrally coordinated. Whereas 1 and 3 are built up from isolated complex ions, 2 comprises a coordination polymer, in which the Fe(II) ion is coordinated by two oxygen atoms of two water molecules in a trans orientation and four nitrogen donor atoms of the [B(CN)(4)](-) groups, which bridge between neighboring iron ions. The iron(III) ion in 3 is in a perfect octahedral environment, which is formed by the O atoms of 6 molecules of water. The single-crystal X-ray structures, vibrational spectra, thermal properties, solubilities, and electrochemical characteristics are reported and compared with those of other known tetracyanidoborates.     

Monomeric, trimeric, and tetrameric transition metal complexes (Mn, Fe, Co) containing N,N-bis(2-pyridylmethyl)-2-aminoethanol/-ate: preparation, crystal structure, molecular magnetism and oxidation catalysis

The reaction of N,N-bis(2-pyridylmethyl)-2-aminoethanol (bpaeOH), NaSCN/NaN(3), and metal (M) ions [M = Mn(II), Fe(II/III), Co(II)] in MeOH, leads to the isolation of a series of monomeric, trimeric, and tetrameric metal complexes, namely [Mn(bpaeOH)(NCS)(2)] (1), [Mn(bpaeO)(N(3))(2)] (2), [Fe(bpaeOH)(NCS)(2)] (3), [Fe(4)(bpaeO)(2)(CH(3)O)(2)(N(3))(8)] (4), [Co(bpaeOH)(NCS)(2)] (5), and [Co(3)(bpaeO)(2)(NO(3))(N(3))(4)](NO(3)) (6). These compounds have been investigated by single crystal X-ray diffractometry and magnetochemistry. In complex 1 the Mn(II) is bonded to one bpaeOH and two thiocyanate ions, while in complex 2 it is coordinated to a deprotonated bpaeO(-) and two azide ions. The oxidation states of manganese ions are 2+ for 1 and 3+ for 2, respectively, indicating that the different oxidation states depend on the type of binding anions. The structures of monomeric iron(II) and cobalt(II) complexes 3 and 5 with two thiocyanate ions are isomorphous to that of 1. Compounds 1, 2, 3, and 5 exhibit high-spin states in the temperature range 5 to 300 K. 4 contains two different iron(III) ions in an asymmetric unit, one is coordinated to a deprotonated bpaeO(-), an azide ion, and a methoxy group, and the other is bonded to three azide ions and two oxygens from bpaeO(-) and a methoxy group. Two independent iron(III) ions in 4 form a tetranuclear complex by symmetry. 4 displays both ferromagnetic and antiferromagnetic couplings (J = 9.8 and -14.3 cm(-1)) between the iron(III) ions. 6 is a mixed-valence trinuclear cobalt complex, which is formulated as Co(III)(S = 0)-Co(II)(S = 3/2)-Co(III)(S = 0). The effective magnetic moment at room temperature corresponds to the high-spin cobalt(II) ion (～4.27 μ(B)). Interestingly, 6 showed efficient catalytic activities toward various olefins and alcohols with modest to excellent yields, and it has been proposed that a high-valent Co(V)-oxo species might be responsible for oxygen atom transfer in the olefin epoxidation and alcohol oxidation reactions.