Magnetic properties of cyano-bridged Ln3+-M3+ complexes. Part I: trinuclear complexes (Ln3+ = La, Ce, Pr, Nd, Sm; M3+ = FeLS, Co) with bpy as blocking ligand

The reaction of Ln(NO3)3(aq) with K3[Fe(CN)6] or K3[Co(CN)6] and 2,2'-bipyridine in water/ethanol led to eight trinuclear complexes: trans-[M(CN)4(mu-CN)2{Ln(H2O)4(bpy)2}2][M(CN)6].8H2O (M = Fe3+ or Co3+, Ln = La3+, Ce3+, Pr3+, Nd3+, and Sm3+). The structures for the eight complexes [La2Fe] (1), [Ce2Fe] (2), [Pr2Fe] (3), [Nd2Fe] (4), [Ce2Co] (5), [Pr2Co] (6), [Nd2Co] (7), and [Sm2Co] (8) have been solved; they crystallize in the triclinic space group P and are isomorphous. They exhibit a supramolecular 3D architecture through hydrogen bonding and pi-pi stacking interactions. A stereochemical study of the nine-vertex polyhedra of the lanthanide ions, based on continuous shape measures, is presented. No significant magnetic interaction was found between the lanthanide(III) and the iron(III) ions.     

新型Schiff碱单核及异双核配合物的合成及光谱特征

首次报道了新型Schiff碱配合物--双[N,N'-亚乙基-2,2'-(苯亚甲基)二(3,4-二甲基吡咯-5-醛缩亚胺)]合单金属配合物MH₂L[M=Mn(Ⅱ),Fe(Ⅲ)Cl,Cr(Ⅲ)Cl,Cu(Ⅱ),Co(Ⅱ),Ni(Ⅱ),Zn(Ⅱ)]及异双金属配合物MnML[M=Fe(Ⅲ)Cl,Cr(Ⅲ)Cl,Cu(Ⅱ),Co(Ⅱ),Ni(Ⅱ),Zn(Ⅱ)]的合成方法及光谱特征.     

Metal Cyanide Ions Mx(CN)y]+,- in the gas phase: M = Fe,Co, Ni,Zn, Cd,Hg, Fe + Ag,Co + Ag

The generation of metal cyanide ions in the gas phase by laser ablation of M(CN)(2) (M = Co, Ni, Zn, Cd, Hg), Fe(III)[Fe(III)(CN)(6)] x xH(2)O, Ag(3)[M(CN)(6)] (M = Fe, Co), and Ag(2)[Fe(CN)(5)(NO)] has been investigated using Fourier transform ion cyclotron resonance mass spectrometry. Irradiation of Zn(CN)(2) and Cd(CN)(2) produced extensive series of anions, [Zn(n)(CN)(2n+1)](-) (1 < or = n < or = 27) and [Cd(n)(CN)(2n+1)](-) (n = 1, 2, 8-27, and possibly 29, 30). Cations Hg(CN)(+) and [Hg(2)(CN)(x)](+) (x = 1-3), and anions [Hg(CN)(x)](-) (x = 2, 3), are produced from Hg(CN)(2). Irradiation of Fe(III)[Fe(III)(CN)(6)] x xH(2)O gives the anions [Fe(CN)(2)](-), [Fe(CN)(3)](-), [Fe(2)(CN)(3)](-), [Fe(2)(CN)(4)](-), and [Fe(2)(CN)(5)](-). When Ag(3)[Fe(CN)(6)] is ablated, [AgFe(CN)(4)](-) and [Ag(2)Fe(CN)(5)](-) are observed together with homoleptic anions of Fe and Ag. The additional heterometallic complexes [AgFe(2)(CN)(6)](-), [AgFe(3)(CN)(8)](-), [Ag(2)Fe(2)(CN)(7)](-), and [Ag(3)Fe(CN)(6)](-) are observed on ablation of Ag(2)[Fe(CN)(5)(NO)]. Homoleptic anions [Co(n)(CN)(n+1)](-) (n = 1-3), [Co(n)(CN)(n+2)](-) (n = 1-3), [Co(2)(CN)(4)](-), and [Co(3)(CN)(5)](-) are formed when anhydrous Co(CN)(2) is the target. Ablation of Ag(3)[Co(CN)(6)] yields cations [Ag(n)(CN)(n-1)](+) (n = 1-4) and [Ag(n)Co(CN)(n)](+) (n = 1, 2) and anions [Ag(n)(CN)(n+1)](-) (n = 1-3), [Co(n)(CN)(n-1)](-) (n = 1, 2), [Ag(n)Co(CN)(n+2)](-) (n = 1, 2), and [Ag(n)Co(CN)(n+3)](-) (n = 0-2). The Ni(I) species [Ni(n)(CN)(n-1)](+) (n = 1-4) and [Ni(n)(CN)(n+1)](-) (n = 1-3) are produced when anhydrous Ni(CN)(2) is irradiated. In all cases, CN(-) and polyatomic carbon nitride ions C(x)N(y)(-) are formed concurrently. On the basis of density functional calculations, probable structures are proposed for most of the newly observed species. General structural features are low coordination numbers, regular trigonal coordination stereochemistry for d(10) metals but distorted trigonal stereochemistry for transition metals, the occurrence of M-CN-M and M(-CN-)(2)M bridges, addition of AgCN to terminal CN ligands, and the occurrence of high spin ground states for linear [M(n)(CN)(n+1)](-) complexes of Co and Ni.     

Magnetism of cyano-bridged hetero-one-dimensional Ln3+-M3+ complexes (Ln3+ = Sm,Gd, Yb; M3+ = FeLS,Co)

The reaction of Ln(NO(3))(3).aq with K(3)[Fe(CN)(6)] or K(3)[Co(CN)(6)] and 2,2'-bipyridine in water led to five one-dimensional complexes: trans-[M(CN)(4)(mu-CN)(2)Ln(H(2)O)(4) (bpy)](n)().XnH(2)O.1.5nbpy (M = Fe(3+) or Co(3+); Ln = Sm(3+), Gd(3+), or Yb(3+); X = 4 or 5). The structures for [Fe(3)(+)-Sm(3+)] (1), [Fe(3)(+)-Gd(3+)] (2), [Fe(3)(+)-Yb(3+)] (3), [Co(3)(+)-Gd(3+)] (4), and [Co(3)(+)-Yb(3+)] (5) have been solved; they crystallize in the triclinic space P1 and are isomorphous. The [Fe(3+)-Sm(3+)] complex is a ferrimagnet, its magnetic studies suggesting the onset of weak ferromagnetic 3-D ordering at 3.5 K. The [Fe(3+)-Gd(3+)] interaction is weakly antiferromagnetic. The isotropic nature of Gd(3+) allowed us to evaluate the exchange interaction (J = 0.77 cm(-)(1)).     

A Series of Mononuclear Complexes Constructed from Transition Metals and Amino Acid Derived Ligands: Syntheses, Structures and Photoluminescence

Eight neutral mononuclear complexes constructed from transition metals （M = Co（Ⅱ）, Ni（Ⅱ）, Cu（Ⅱ）, Zn（Ⅱ）, Cd（Ⅱ）） and ligands N-（2-pyridylmethyl）-L-phenylalanine （L-Hpmpa） and N-（2-pyridylmethyl）-L-tyrosine （L-Hpmtyr） have been synthesized by both hydrothermal and conventional room temperature reactions. Four of them have been structurally characterized by single-crystal X-ray diffractions. They are： [Co（L-pmpa）2·2H2O] 1, [Ni（L-pmpa）2·2H2O] 2, [Cu（L-pmpa）2·2H2O] 3 and [Cu（L-pmtyr）2·2H2O] 4. Single-crystal X-ray analysis, IR and elemental analysis revealed that complexes 1, 2 and 3 are isostructural. Powder X-ray diffraction, IR and elemental analysis revealed that complexes 4, 5 （Zn[L-pmtyr]2·2H2O）, 6 （Cd[L-pmtyr]2·2H2O）, 7 （Co[L-pmtyr]2·2H2O） and 8 （Ni[L-pmtyr]2·2H2O） are isostructural. The photoluminescence properties of L-Hpmtyr ligand, compounds 5 and 6 were also investigated.     

Unusual reactivity of methylene group adjacent to pyridine-2-carboxamido moiety in iron(III) and cobalt(III) complexes

The Fe(III) and Co(III) complexes of the ligand N-(2-picolyl)picolinamide (pmpH; H represents the dissociable amide hydrogen), namely, [Fe(pmp)(2)]BF(4) (1) and [Co(pmp)(2)]ClO(4) (2), have been synthesized and structurally characterized. The [bond]CH(2)[bond] moiety of pmp(-) in [M(pmp)(2)](+) (M = Fe, Co) is very reactive and is readily converted to carbonyl (C[double bond]O) group upon exposure to dioxygen. Such conversion results in [M(bpca)(2)]ClO(4) complexes (M = Fe (3), Co (5); bpcaH = bis(2-pyridylcarbonyl)amine) which have been characterized by spectroscopy and X-ray diffraction. The structure of 5 is reported here for the first time. The reactivity of the [bond]CH(2)[bond] moiety of pmp(-) has so far precluded the isolation of 1 although other metal complexes of pmp(-) have been reported years ago. The CH(2) --> C[double bond]O transformation arises from the tendency of the coordinated pmp(-) ligand to achieve further conjugation in the ligand framework and provides a better way to synthesize the metal complexes of bpcaH ligand. Reaction of 3 with NaH affords Fe(II) complex [Fe(bpca)(2)] (4) without any reduction of the ligand frame.     

噻吩甲酰基吡唑啉酮缩乙二胺配合物的合成、表征及生物活性

A new ligand N,N′-bis［(1-phenyl-3-methyl-5-oxo-4-pyrazolinyl)-2-thenoylmethylidyne］ethyl-enediimine (HPMTHP)₂en and its five complexes have been sythesized. These complexes have the general formula ［M(PMTHP)₂en］, where M=Cu(Ⅱ), Ni(Ⅱ)     

Schiff碱单核及双核配合物拟酶催化性能的研究

系统地研究了新型Schiff碱单核及双核配合物在拟酶催化PhIO单加氧化环己烷反应中的催化性能.结果表明,双核配合物MnML{M=Mn(Ⅱ),Fe(Ⅲ)Cl,Cr(Ⅲ)Cl,Cu(Ⅱ),Co(Ⅱ),Ni(Ⅱ),Zn(Ⅱ);L=双[N,N'亚乙基2,2'(苯亚甲基)二(3,4二甲基吡咯5醛缩亚胺)]}的催化活性比对应的单核配合物MnH₂L与MH₂L之混合物的催化活性高.因此,我们认为在双核配合物中两金属离子间存在协同作用,并发现这种协同作用一般随双核配合物中成单d电子数增加而增大.     

Transition metal complexes bearing 2,6-bis(imino)pyridyl: Synthesis,structure, ethylene polymerization/ oligomerization studies

A series of new complexes {2,6-bis[1-((2-methyl-4-methoxyphenyl)imino)ethyl]pyridine}Cl₂ [M=Fe(II) (2), Co(II) (3), Ni(II) (4), Cu(II) (5), Zn(II) (6)] have been synthesized. At 25°C, using 500 equiv of methylaluminoxane (MAO), the activities of Fe(II), Co(II) catalysts can reach 4.02 ×10⁶ g/mol-Fehatm for ethylene polymerization and 3.98×10⁵ g/mol-Cohatm for ethylene oligomerization. The effects of polymerization conditions such as reaction temperature, Al/M molar ratio and time on the activity of catalyst have been explored.     

Transition metal complexes bearing 2,6-bis(imino)pyridyl: Synthesis,structure, ethylene polymerization/ oligomerization studies

A series of new complexes {2,6-bis[1-((2-methyl-4-methoxyphenyl)imino)ethyl]pyridine}Cl₂ [M=Fe(II) (2), Co(II) (3), Ni(II) (4), Cu(II) (5), Zn(II) (6)] have been synthesized. At 25°C, using 500 equiv of methylaluminoxane (MAO), the activities of Fe(II), Co(II) catalysts can reach 4.02 ×10⁶ g/mol-Fehatm for ethylene polymerization and 3.98×10⁵ g/mol-Cohatm for ethylene oligomerization. The effects of polymerization conditions such as reaction temperature, Al/M molar ratio and time on the activity of catalyst have been explored.

     

异双核X-M之间的磁耦合交换作用: Keggin型杂多酸衍生物[M(H2O)XW11O39]7-(X=FeⅢ, CoⅢ; M=CoⅡ)的密度泛函研究

采用DFT-BS方法研究异双核的Keggin型杂多酸衍生物[M(H2O)XW11O39]7-(Ⅰ: X=FeⅢ, M=CoⅡ; Ⅱ: X=CoⅢ, M=CoⅡ)的磁耦合作用, 计算得到耦合常数(J)为负值, 表明所研究体系具有反铁磁性; J值大小顺序为|J(Ⅰ)|<|J(Ⅱ)|, 说明磁耦合作用增强; 体系Ⅰ与Ⅱ相比, X由FeⅢ变成CoⅢ, M不变, 桥氧原子Ob和Ob2(O′b2)上的自旋密度增大, 进一步从相关BS态的磁轨道比较得出, 体系Ⅱ中轨道重叠程度大于体系Ⅰ, 结果使X-M之间的反铁磁耦合作用加强.     

Molecular and electronic structures of bis(pyridine-2,6-diimine)metal complexes [ML2](PF6)n (n = 0, 1, 2, 3; M = Mn, Fe, Co, Ni, Cu, Zn)

A series of mononuclear, octahedral first-row transition metal ion complexes mer-[M(II)L0(2)](PF6)2 containing the tridentate neutral ligand 2,6-bis[1-(4-methoxyphenylimino)ethyl]pyridine (L0) and a Mn(II), Fe(II), Co(II), Ni(II), Cu(II), or Zn(II) ion have been synthesized and characterized by X-ray crystallography. Cyclic voltammetry and controlled potential coulometry show that each dication (except those of Cu(II) and Zn(II)) can be reversibly one-electron-oxidized, yielding the respective trications [M(III)L0(2)]3+, and in addition, they can be reversibly reduced to the corresponding monocations [ML2]+ and the neutral species [ML2]0 by two successive one-electron processes. [MnL2]PF6 and [CoL2]PF6 have been isolated and characterized by X-ray crystallography; their electronic structures are described as [Mn(III)L1(2)]PF6 and [Co(I)L0(2)]PF6 where (L1)1- represents the one-electron-reduced radical form of L0. The electronic structures of the tri-, di-, and monocations and of the neutral species have been elucidated in detail by a combination of spectroscopies: UV-vis, NMR, X-band EPR, Mossbauer, temperature-dependent magnetochemistry. It is shown that pyridine-2,6-diimine ligands are noninnocent ligands that can be coordinated to transition metal ions as neutral L0 or, alternatively, as monoanionic radical (L1)1-. All trications are of the type [M(III)L0(2)]3+, and the dications are [M(II)L0(2)]2+. The monocations are described as [Mn(III)L1(2)]+ (S = 0), [Fe(II)L0L1]+ (S = 1/2), [Co(I)L0(2)]+ (S = 1), [Ni(I)L0(2)]+ (S = 1/2), [Cu(I)L0(2)]+ (S = 0), [Zn(II)L1L0]+ (S = 1/2) where the Mn(II) and Fe(II) ions are low-spin-configurated. The neutral species are described as [Mn(II)L1(2)]0, [Fe(II)L1(2)]0, [Co(I)L0L1]0, [Ni(I)L0L1]0, and [Zn(II)L1(2)]0; their electronic ground states have not been determined.     

Nine non-symmetric pyrazine-pyridine imide-based complexes: reversible redox and isolation of [M(II/III)(pypzca)2](0/+) when M = Co, Fe

The non-symmetric imide ligand Hpypzca (N-(2-pyrazylcarbonyl)-2-pyridinecarboxamide) has been deliberately synthesised and used to produce nine first row transition metal complexes: [M(II)(pypzca)(2)], M = Zn, Cu, Ni, Co, Fe; [M(III)(pypzca)(2)]Y, M = Co and Y = BF(4), M = Fe and Y = ClO(4); [Cu(II)(pypzca)(H(2)O)(2)]BF(4), [Mn(II)(pypzca)(Cl)(2)]HNEt(3). These are the first deliberately prepared complexes of a non-symmetric imide ligand. X-ray crystal structures of [Cu(II)(pypzca)(2)]·H(2)O, [Co(II)(pypzca)(2)], [Co(III)(pypzca)(2)]BF(4), [Cu(II)(pypzca)(H(2)O)(2)]BF(4)·H(2)O and [Mn(II)(pypzca)Cl(2)]HNEt(3) show that each of the (pypzca)(-) ligands binds in a meridional fashion via the N(3) donors. In the first three complexes, two such ligands are bound such that the 'spare' pyrazine nitrogen atoms are positioned approximately orthogonally to one another and also to the imide oxygen atoms. In MeCN the [M(II/III)(pypzca)(2)](0/+) complexes, where M = Ni, Co or Fe, exhibit one reversible metal based M(II/III) process and two distinct, quasi-reversible ligand based reduction processes, the latter also observed for M(II) = Zn. [Mn(II)(pypzca)Cl(2)]HNEt(3) displays a quasi-reversible oxidation process in MeCN, along with several irreversible processes. Both copper(II) complexes show only irreversible processes. Variable temperature magnetic measurements show that [Fe(III)(pypzca)(2)]ClO(4) undergoes a gradual spin crossover from partially high spin at 298 K (3.00 BM) to fully low spin at 2 K (1.96 BM), and that [Co(II)(pypzca)(2)] remains high spin from 298 to 4 K. All of the complexes are weakly coloured, other than [Fe(II)(pypzca)(2)] which is dark purple and absorbs strongly in the visible region.     

Synthesis, structure and DFT study of dinuclear iron, cobalt and nickel complexes with cyclopentadienyl-metal moieties

Reactions of 1,1'-bis(dipheny1phosphino)cobaltocene with Co(PMe(3))(4), Ni(PMe(3))(4), Fe(PMe(3))(4), Ni(COD)(2), FeMe(2)(PMe(3))(4) or NiMe(2)(PMe(3))(3) afford a series of novel dinuclear complexes [((Me(3)P)[lower bond 1 start]Co(η(5)-C(5)H(4)[upper bond 1 start]PPh(2)))((Me(3)P)M[upper bond 1 end](η(5)-C(5)H(4)P[lower bond 1 end]Ph(2)))] (M = Co(1), Ni(2) and Fe(3)) [Co(η(5)-C(5)H(4)[upper bond 1 start]PPh(2))(2)Ni[upper bond 1 end](COD)](4), [Co(η(5)-C(5)H(4)[upper bond 1 start]PPh(2))(2)Ni[upper bond 1 end](PMe(3))(2)] (5) and [((Me(3)P)[lower bond 1 start]Co(Me)(η(5)-C(5)H(4)[upper bond 1 start]PPh(2)))((Me(3)P)Fe[upper bond 1 end](Me)(η(5)-C(5)H(4)P[lower bond 1 end]Ph(2)))] (6). Reactions of 1,1'-bis(dipheny1phosphino)ferrocene with Ni(PMe(3))(4), NiMe(2)(PMe(3))(3), or Co(PMe(3))(4) gives rise to complexes [Fe(η(5)-C(5)H(4)[upper bond 1 start]PPh(2))(2)M[upper bond 1 end](PMe(3))(2)] (M = Ni (7), Co (8)). The complexes 1-8 were spectroscopically investigated and studied by X-ray single crystal diffraction. The possible reaction mechanisms and structural characteristics are discussed. Density functional theory (DFT) calculations strongly support the deductions.     

Triton X-100微乳液体系中铁的萃取与分离

近年来 ,在以表面活性剂分子有序组合油包水 (W/O)微乳液体系中进行萃取分离已引起人们的重视 [1～ 3] .本文根据微乳液体系较相应胶束有更低的表面张力和更高增溶量的特性 ,首次利用非离子型水包油 (O/W)壬基酚聚氧乙烯醚(Triton X- 1 0 0 )微乳液在无机盐硫酸铵的存在下萃取分离铁 ,与传统的有机溶剂萃取分离方法比较 ,此法具有不挥发、无毒、快速和操作简单等特点 ;与高聚物水溶液体系萃取 ,有相同的萃取效果 ,但药品用量相对减少 .GBC932 AA原子吸收分光光度计 (澳大利亚 ) ;p Hs- 2 5酸度计 (上海雷磁仪器厂 ) .铝试剂为质量分数 …     

Dinuclear amine-thiophenolate complexes coligated by ferrocenemonocarboxylate and 1,1'-ferrocenedicarboxylate anions: preparation, characterization and structures of trinuclear [LMII 2(O2CC5H4FeCp)]+ and Pentanuclear [(LMII 2)2(O2CC5H4)2Fe]2+ complexes (M=Co, Ni, Zn)

A series of novel tri- and pentanuclear complexes composed of dinuclear LM(2) units (M=Co, Ni, Zn; L=24-membered macrocyclic hexaazadithiophenolate ligand) and ferrocenecarboxylate ([CpFeC(5)H(4)CO(2)](-)) or 1,1'-ferrocenedicarboxylate ([Fe(C(5)H(4)CO(2))(2)](2-)) groups is reported. The complexes [LM(II) (2)(O(2)CC(5)H(4)FeCp)](+) (M=Co (6), Ni (7), Zn (8)) and [(LM(II) (2))(2)(O(2)CC(5)H(4))(2)Fe](2+) (M=Co (9), Ni (10)) have been prepared by substitution reactions from labile [LM(II) (2)L'](+) precursors (L'=Cl, OAc) and the respective ferrocenecarboxylate anions in methanol. Mixed-valent [(LCo(II)Co(III))(2)(O(2)CC(5)H(4))(2)Fe](4+) (11) was prepared by oxidation of 9 with bromine. Complexes 7[BPh(4)], 8[BPh(4)], 9[BPh(4)](2), 10[BPh(4)](2), and 11[ClO(4)](4) have been characterized by X-ray crystallography; showing that the ferrocenyl carboxylates act as bidentate (7, 8) or bis-bidentate (9-11) bridging ligands towards one or two bioctahedral LM(2) subunits, respectively. The structures are retained in solution as indicated by NMR spectroscopic studies on the diamagnetic Zn(2)Fe complex 8[ClO(4)]. Electrochemical studies reveal significant anodic potential shifts for the oxidation potential of the ferrocenyl moieties upon complexation and the magnitude of the potential shift appears to correlate with the charge of the LM(2) subunits. This is qualitatively explained in terms of destabilizing electrostatic (Coulomb) interactions between the M(2+) ions of the LM(2) unit and the proximate ferrocenium fragment. An analysis of the temperature-dependent magnetic susceptibility data for 10[BPh(4)](2) shows the presence of weak ferromagnetic magnetic exchange interactions between the Ni(II) ions in the LNi(2) units. The exchange coupling across the ferrocenedicarboxylate bridge is negligible.     

Electronic structure of nitric oxide adducts of bis(diaryl-1,2-dithiolene)iron compounds: four-membered electron-transfer series [Fe(NO)(L)2]z (z = 1+, 0, 1-, 2-)

Four members of the electron-transfer series [Fe(NO)(S(2)C(2)R(2))2]z (z = 1+, 0, 1-, 2-) have been isolated as solid materials (R = p-tolyl): [1a](BF4), [1a]0, [Co(Cp)2][1a], and [Co(Cp)2]2[1a]. In addition, complexes [2a]0 (R = 4,4-diphenyl), [3a]0 (R = p-methoxyphenyl), [Et(4)N][4a] (R = phenyl), and [PPh(4)][5a] (R = -CN) have been synthesized and the members of each of their electron-transfer series electrochemically generated in CH(2)Cl(2) solution. All species have been characterized electro- and magnetochemically. Their electronic, M?ssbauer, and electron paramagnetic resonance spectra as well as their infrared spectra have been recorded in order to elucidate the electronic structure of each member of the electron-transfer series. It is shown that the monocationic, neutral, and monoanionic species possess an {FeNO}6 (S = 0) moiety where the redox chemistry is sulfur ligand-based, (L)2-(L*)1-: [Fe(NO)(L*)2]+ (S = 0), [Fe(NO)(L*)(L)]0 <--> [Fe(NO)(L)(L*)]0 (S = 1/2), [Fe(NO)(L)2]- (S = 0). Further one-electron reduction generates a dianion with an {FeNO}7 (S = 1/2) unit and two fully reduced, diamagnetic dianions L2-: [Fe(NO)(L)2]2- (S = 1/2).     

Synthesis, characterization, and reactivity studies of heterodinuclear complexes modeling active sites in purple acid phospatases

To model the heterodinuclear active sites in plant purple acid phosphatases, a mononuclear synthon, [Fe(III)(H(2)IPCPMP)(Cl(2))][PF(6)] (1), has been generated in situ from the ligand 2-(N-isopropyl-N-((2-pyridyl)methyl)aminomethyl)-6-(N-(carboxylmethyl)-N-((2-pyridyl)methyl)amino methyl)-4-methylphenol (IPCPMP) and used to synthesize heterodinuclear complexes of the formulas [Fe(III)M(II)(IPCPMP)(OAc)(2)(CH(3)OH)][PF(6)] (M = Zn (2), Co (3), Ni (4), Mn (5)), [Fe(III)Zn(II)(IPCPMP)(mpdp)][PF(6)] (6) (mpdp = meta-phenylene-dipropionate), and [Fe(III)Cu(II)(IPCPMP) (OAc)}(2)(μ-O)][PF(6)] (7). Complexes 2-4, 6, and 7 have been crystallographically characterized. The structure of 6 is a solid state coordination polymer with heterodinuclear monomeric units, and 7 is a tetranuclear complex consisting of two heterodinuclear phenolate-bridged Fe(III)Cu(II) units bridged through a μ-oxido group between the two Fe(III) ions. Mo?ssbauer spectra confirm the presence of high spin Fe(III) in an octahedral environment for 1, 3, and 5 while 2 and 4 display relaxation effects. Magnetic susceptibility measurements indicate weak antiferromagnetic coupling for 3, 4, and 5 and confirm the assignment of the metal centers in 2-5 as high spin Fe(III)-M(II) (M = Zn, Co (high spin), Ni (high spin), Mn (high spin)). Complexes 2-5 are intact in acetonitrile solution as indicated by IR spectroscopy (for 2-4) and electrospray ionization mass spectrometry (ESI-MS) but partly dissociate to hydroxide species and a mononuclear complex in water/acetonitrile solutions. UV-vis spectroscopy reveal pH-dependent behavior, and species that form upon increasing the pH have been assigned to μ-hydroxido-bridged Fe(III)M(II) complexes for 2-5 although 2 and 3 is further transformed into what is propsed to be a μ-oxido-bridged tetranuclear complex similar to 7. Complexes 2-5 enhance phosphodiester cleavage of 2-hydroxy-propyl-p-nitrophenyl phosphate (HPNP) and bis(2,4-dinitrophenyl)phosphate (BDNPP), but the reactivities are different for different complexes and generally show strong pH dependence.     

系列Co-M(M=Cd,Zn, Co)配位聚合物的合成、结构及光电性能

采用水热合成方法得到了3个Co-M配聚物: [CoCd(mal)₂(H₂O)₄]_n(1), [CoZn(mal)₂(H₂O)₄]_n(2) 和[Co₂(mal)₂(H₂O)₄]_n(3)(mal=malonate). 通过X射线单晶衍射确定了各配聚物的结构. 3个配聚物都是由丙二酸构筑并具有2D层状结构, 通过氢键进一步将2D层网联成3D无限网络结构. 通过表面光电压谱(SPS)对3个配聚物的表面光电性能进行了重点研究, 并与其相应的UV-Vis吸收光谱进行了对比. 结果表明, 这3个配聚物在300~600 nm范围内均表现出正的光伏响应, 而且SPS和UV-Vis光谱之间具有较好的对应关系.     

联氨在d-过渡金属配合物MTP(o-NO2)TBP修饰石墨电极上的催化氧化研究

研究了N₂H₄在间-四(邻-硝基苯基)四苯并卟啉铁(Ⅲ)、钴(Ⅱ)、锌(Ⅱ)和镍(Ⅱ)配合物[MTP(o-NO₂)TBP,简称MTBP]修饰石墨电极上的催化电氧化反应,测得该系列金属四苯并卟啉的催化活性的顺序为Co(Ⅱ)TBP>ClFe(Ⅲ)TBP>Ni(Ⅱ)TBP>Zn(Ⅱ)TBP≈石墨,考察了Co(Ⅱ)TBP和ClFe(Ⅲ)TBP催化联氨电氧化反应的动力学过程.结果表明,OH^-和N₂H₄在ClFe(Ⅱ)TBP修饰电极上的反应级数分别为2和1,而在Co(Ⅱ)TBP修饰电极上的均为1.根据电化学参数提出了可能的反应机理.