Cd(ATZ)4( H2O)2] ( PA)2· 2H2O的合成、晶体结构和热分解机理研究

合成了以 5 -氨基四唑为配体的镉配合物 [Cd(ATZ) 4(H2 O) 2 ](PA) 2 ·2H2 O ,并对其进行了晶体结构测定 .测定结果表明 ,该配合物分子具有中心对称性 ,每个Cd2 +分别与 2个水分子中的氧原子和 4个 5 -氨基四唑 (ATZ)分子中的 4-位氮原子配位 ,形成六配位畸变八面体结构 ;在配合物分子间存在大量氢键 ,增加了整个晶体结构的稳定性 .通过DSC和TG -DTG分析 ,提出了标题化合物的热分解机理     

由4-氯-6-[2-(吡嗪-2-基亚甲基)肼基]嘧啶构筑的一维银配合物及其抗氧化和抑菌性能

由4-氯-6-[2-(吡嗪-2-基亚甲基)肼基]嘧啶(HL)和硝酸银合成了一维链状配位聚合物[Ag(C_(10)H_9N_6Cl)(NO_3)]_n(1)。在配合物1中,中心Ag离子与来自配体吡嗪环上的N5原子及另一配体上的N1、N4、N6原子进行配位,形成了锯齿形的一维链状结构。此外,锯齿形一维链通过N—H…O和N—H…N氢键相互作用及π-π堆积形成了三维的超分子结构。研究结果表明,与配体HL相比配合物1对超氧负离子和羟基自由基具有更强的自由基清除效能;配合物1对不同细菌的抗菌效果也优于配体HL。     

4-[(N-甲基-N-羟乙基)氨基]苯甲醛缩氨基硫脲及其过渡金属配合物的合成及表征

本文报道了4－[(N－甲基－N－羟乙基）氨基]苯甲醛缩氨基硫脲（HL）及其金属配合物的合成,通过元素分析、红外光谱、紫外、核磁共振对配体和配合物进行了表征。配合物的组成为ML2（M=Ni(Ⅱ）、Cu（Ⅱ）、Zn（Ⅱ）、Cd（Ⅱ）、Pd（Ⅱ）。晶体结构分析表明配体分子中除了羟乙基偏离平面外,其余各原子几乎在一个平面上。晶体结构中存在N－H…O（N1…O1）和O－H…S氢键,形成一个二维网状结构。在与金属离子配合时,配体由硫酮式转变为硫醇式作为负一价二齿配体通过S和β-N与金属离子螯合,形成稳定的中性配合物。     

四核Cu(Ⅰ)配合物[Cu4(imdt)9](NO3)4·6H2O的合成与晶体结构

近年来,硫脲类金属配合物在配位化学、生物化学、医药等领域的研究一直受到广泛重视[1,2]。四氢化咪唑-2-硫酮(imdt)又称乙撑硫脲,是乙撑双二硫代氨基甲酸酯类农药的代谢产物。它属于硫酰胺杂环化合物,含—N(H)—C(=S)—=—N=C(—SH)—结构互变活性基团,表现出配位多样性,与金属铜可以形成单核[3]和双核[4,5]配合物。本文合成了四核Cu(I)配合物[Cu4(imdt)9](NO3)4·6H2O,对该配合物进行了元素分析和红外光谱表征,用单晶X-射线衍射测定了晶体结构。1实验部分1·1试剂与仪器配体四氢化咪唑-2硫酮(C3H6N2S,imdt)按文献合成[6],其它药品…     

3-乙基-2-乙酰吡嗪缩4-甲基氨基硫脲Cu(Ⅱ)配合物的合成、结构和DNA结合性质（英文）

合成并通过单晶衍射、元素分析、红外光谱表征了配合物[Cu(L)Br]·DMF (1),[Cu(L)Cl]·2H2O (2)和[Cu2(L)2(SO4)]·H2O·CH3OH (3)的结构(HL为3-乙基-2-乙酰吡嗪缩4-甲基氨基硫脲)。单晶衍射结果表明,配合物1和2中的Cu(Ⅱ)离子与来自1个缩氨基硫脲阴离子配体的N2S给体及1个卤素阴离子配位(1和2中分别为溴离子和氯离子),采取扭曲的平面正方形配位构型。而双核配合物3中,2个Cu(Ⅱ)中心由2个缩氨基硫脲配体的2个硫原子桥联形成Cu2S2簇,Cu…Cu距离为0.318 0 nm。每个Cu(Ⅱ)离子还与来自同一缩氨基硫脲配体的2个氮原子和处于外轴向位置η2-SO42-的1个氧原子配位,配位构型为扭曲的四方锥。此外,荧光光谱结果表明,配合物与DNA的相互作用强于配体。     

3-((4，6-二甲基-2-嘧啶基)硫代)-丙酸和菲咯啉三元稀土配合物的晶体结构和发光性能

制备了以3-((4,6-二甲基-2-嘧啶基)硫代)-丙酸(HL)和菲咯啉(Phen)为配体的2个三元稀土配合物[Eu(L)₃(Phen)]₂·2H₂O(1)和[Tb(L)₃(Phen)]₂·2H₂O(2),并对其结构进行了表征。单晶X射线衍射分析表明它们是同构的。2个稀土离子(Ln)由4个羧酸配体桥接,形成二聚体排列。其余2个羧酸配体和Phen以双齿螯合方式与Ln配位。Ln的配位数为9,具有扭曲的单端方形反棱柱配位多面体构型。固态光致发光测试表明,这2种配合物都显示了金属中心的特征发射带。     

[Zn(AZT)4(H2O)2](PA)2∙4H2O和[Zn(AZT)2(H2O)4](HTNR)2∙4H2O (AZT = 3-叠氮-1,2,4-三唑, HPA = 苦味酸, H2TNR = 斯蒂芬酸)的合成、晶体结构、热分解及感度性能

以3-叠氮-1,2,4-三唑为配体，PA–（苦味酸根）或HTNR–（2,4,6-三硝基间苯二酚脱去一个羟基的质子后形成的离子）为外阴离子，制备得到了两种新的配合物：[Zn(AZT)4(H2O)2](PA)2∙4H2O和[Zn(AZT)2(H2O)4](HTNR)2∙4H2O。[Zn(AZT)4(H2O)2](PA)2∙ 4H2O的X射线晶体数据表明，中心Zn2+离子与来自4个AZT分子的N原子和2个H2O分子的O原子配位；而对于[Zn(AZT)2(H2O)4](HTNR)2∙4H2O来说，6个配位原子来自2个AZT分子的N原子和4个H2O分子的O原子。在两种配合物中，AZT配体分子的配位点都是三唑环上的4位N原子。H2O分子对于分子间氢键的形成起到了重要的作用，在分子间氢键的作用下形成了配合物的晶体结构。在[Zn(AZT)4(H2O)2](PA)2∙4H2O的晶体结构中，还存在错位面对面π-π堆积作用，它对于晶体结构的形成和稳定性也起到了重要作用。TG-DTG和DSC分析结果显示，[Zn(AZT)2(H2O)4](HTNR)2∙4H2O的热分解过程不如[Zn(AZT)4(H2O)2](PA)2∙4H2O剧烈，原因在于前者分子中含有较多配位水分子和较少AZT配体分子。感度测试结果表明，[Zn(AZT)4(H2O)2](PA)2∙4H2O有一定的火焰感度，而[Zn(AZT)2(H2O)4](HTNR)2∙4H2O却对热不敏感；两种化合物在撞击和摩擦作用下都表现钝感。     

氢键和π-π诱导的三重穿插的二维Zn(Ⅱ)配位聚合物的晶体结构和荧光性能

本文以(4-羧基苄基)-4,4′-二羧基二苯胺(H3L)和1,10-菲罗啉(Phen)为配体,溶剂热合成了一个二维锌配位聚合物[Zn(HL)(Phen)]n(1),对其进行了红外、热重、粉末单晶衍射等表征,配合物属于三斜晶系,空间群P21/c。相邻的Zn(Ⅱ)离子通过连接HL2-和Phen形成一维之字形的链,该一维链通过氢键和π-π作用进一步形成三重穿插的二维超分子结构。此外,还研究了配合物的荧光性能。     

由2-甲基-4-噻唑甲酸构筑的过渡金属配合物的合成、晶体结构及与DNA作用（英文）

以2-甲基-4-噻唑甲酸(HMTZA,C5H5NO2S)为配体合成了3种新型过渡金属配合物[Co(MTZA)2(H2O)2]·3H2O (1),[Cu(MTZA)2(H2O)]·2H2O (2)和[Zn(MTZA)2(H2O)2]·3H2O (3)。对配合物进行了元素分析、红外光谱和热重分析表征,用单晶X射线衍射方法测定了配合物的晶体结构。结果表明,配合物1属于单斜晶系,空间群为P21/n,中心金属Co(Ⅱ)离子的配位数为6,配位构型为略为变形的八面体;配合物2属于三斜晶系,空间群为P1,Cu(Ⅱ)离子的配位构型是一个畸变的四方锥;配合物3属单斜晶系,空间群为P21/n,中心金属Zn(Ⅱ)离子的配位构型为畸变的八面体。用溴化乙锭荧光探针法测定了配体和配合物与DNA作用的荧光光谱,结果显示无论配体还是配合物均能使EB-DNA复合体系发生不同程度的荧光猝灭,且配合物的作用强度远大于配体。     

水杨醛缩氨基硫脲合钴(Ⅱ)的晶体结构及其荧光性质

在甲醇和DMF溶剂里,以Schiff碱水杨醛缩氨基硫脲(简写为HL)和六水二氯化钴合成了配合物[CoHL2].H2O.DMF.在配合物[CoHL2]中,钴(Ⅱ)原子具有扭曲的N2O2S2八面体配位构型,晶体通过分子间氢键作用形成二维的无限网状结构.红外光谱表明,配体在形成配合物后,νS=O,νC=O和νC=N红移.荧光光谱表明,配合物金属对配体n-π*激发引起的荧光发射峰有较大的影响.     

Six Coordination Polymers based on 4‐(1H‐Imidazol‐1‐yl)phthalic Acid: Structural Diversities,Magnetism and Luminescence Properties

The coordination polymers (CPs), [Ni(L)(H₂O)₄]_n ( 1 ), [Co(HL)₂(H₂O)₂]_n ( 2 ), {[Cu(L)(H₂O)₃] · H₂O}_n ( 3 ), [Mn(L)(H₂O)₂]_n ( 4 ), [Cd(L)(H₂O)₂]_n ( 5 ), and {[Zn₂(L)₂] · H₂O}_n ( 6 ), were solvothermally synthesized by employing the imidazol‐carboxyl bifunctional ligand 4‐(1H‐imidazol‐1‐yl) phthalic acid (H₂L). Single‐crystal X‐ray diffraction indicated that the L^2–/HL^– ligands display various coordination modes with different metal ions in 1 – 6 . Complexes 1 and 2 show one‐dimensional (1D) chain structures, whereas complexes 3 – 6 show 2D layered structures. The magnetic properties of these complexes were investigated. Complexes 1 and 3 indicate weak ferromagnetic interactions, whereas complexes 2 and 4 demonstrate antiferromagnetic interactions. In addition, luminescence properties of 5 and 6 were measured and studied in detail.     

Desulfuration and Cyclization of (Z)‐2‐[Amino(pyridine‐2‐yl)methylene]‐ hydrazonecarbothioamide in the Presence of Manganese(II)

The reaction of (Z)‐2‐[amino(pyridine‐2‐yl)methylene]hydrazonecarbothioamide (HAm4DH) with Mn(ClO₄)₂·6H₂O afforded different mononuclear or polynuclear manganese(II) complexes, the nature of which apparently depended on the solvent used. For example, in ethanol a compound of formula [Mn(HAm4DH)₂](ClO₄)₂ ( 1 ) was obtained, where HAm4DH coordinates as a common tridentate NNS donor, but the [Mn(bpy)₂(NCS)₂] complex ( 2 ) (bpy = 2,2'‐bipyridine) has also been obtained – probably due to C–N bond cleavage of the thiosemicarbazone. Nevertheless, in a basic aqueous medium [Mn(bpy)₃](ClO₄)₂·0.5bpy ( 3 ) is formed and there is structural evidence for chemical transformations of the thiosemicarbazone promoted by Mn^II. Thus, the sulfate in {[Mn(py)₄Mn(py)₂(H₂O)₂(μ‐SO₄)₂]·4H₂O}_n ( 4 ) or sulfate and cyclooctasulfur in [Mn(pta)₂(pdo)]₄(SO₄)₂·4H₂O·S₈] ( 5 ), where pta is 3‐(pyridin‐2‐yl)‐1,2,4‐triazol‐5‐amine and pdo is (2R,4R/2S,4S)‐pentane‐2,4‐diolato, arise from the desulfuration and oxidation of the thiosemicarbazone ligand. The structures of complexes 2 to 5 were established by single‐crystal X‐ray diffraction. The formation of pta is the result of the oxidative cyclization of HAm4DH. In the polynuclear complex 4 , the sulfate acts as an (O,O') bridge between alternating Mn(py)₂(H₂O)₂ and Mn(py)₄ centers. In the tetranuclear complex 5 , pta acts as a bischelating ligand through the N‐pyridine and N‐triazole, and pdo act as a bridge between two manganese atoms. It is also noteworthy that in complexes 4 and 5 hydrogen bonds give rise to different self‐assembly behaviour that leads to complicated supramolecular structures.     

Tweaking the affinity of aryl‐substituted diazosalicylato‐ and pyridine ligands towards Zn (II) and its neighbors in the periodic system of the elements,Cu (II) and Cd (II), and their antimicrobial activity

A series of six new Zn (II) compounds, viz., [Zn(HL^ASA)₂(Py)₂] ( 1 ), [Zn(HL^MASA)₂(Py)₂] ( 2 ), [Zn(HL^MASA)₂(4‐MePy)₂] ( 3 ), [Zn(HL^CASA)₂(4‐MePy)₂] ( 4 ), [Zn(HL^BASA)₂(Py)₂] ( 5 ), [Zn(HL^BASA)₂(4‐MePy)₂] ( 6 ) and representative Cu (II) and Cd (II) complexes, viz., [Cu(HL^ASA)₂(Py)₂(H₂O)] ( 7 ) and [Cd(HL^BASA)₂(Py)₃] ( 8 ) [(HL^XASA)^? = para‐substituted 5‐[(E)‐2‐(aryl)‐1‐diazenyl]‐2‐hydroxybenzoate with X = H (ASA), Me (MASA), Cl (CASA) or Br (BASA); Py = pyridine; 4‐MePy = 4‐methylpyridine] have been synthesized and characterized by spectroscopic techniques and single‐crystal X‐ray diffraction analysis. The structural characterization of the compounds revealed distorted tetrahedral ( 1 – 6 ), square‐pyramidal ( 7 ) and pentagonal‐bipyramidal ( 8 ) coordination geometries around the metal atom, in which the aryl‐substituted diazosalicylate ligands are coordinated only through the oxygen atoms of carboxylate groups, either in an anisobidentate or isobidentate mode; meanwhile, the 2‐hydroxy groups of the monoanionic ligand (HL^XASA)^? are involved only in intramolecular O‐H···O hydrogen bonds with the carboxylate function. In the crystal structures of 1 – 8 , the complex molecules are assembled by π‐stacking interactions giving mostly infinite 1D strands. The intermolecular binding in the solid state structures is accomplished by diverse additional non‐covalent contacts including C‐H···O, C‐H···N, C‐H···π, C‐H···Br, O···Br, Br···π and van der Waals contacts. Although the primary and secondary ligands in the Zn (II) complex series 1 – 6 carry different substituents at the periphery (X = H, Me, Cl, Br for (HL^XASA)^? and R = H, Me for 4‐Py‐R), five of the crystal structures were isostructural. Additionally, the antimicrobial activity of the pro‐ligands H₂L^XASA and their Zn (II), Cu (II) and Cd (II) compounds were studied in a comparative manner, showing high sensitivity (IZD ≥ 20) against Bacillus subtilis.     

Oxorhenium(V) Complexes with 1,3,4‐Triphenyl‐1,2,4‐triazol‐5‐ylidene

Reactions of the oxorhenium(V) complexes [ReOX₃(PPh₃)₂] (X = Cl, Br) with the N‐heterocyclic carbene (NHC) 1,3,4‐triphenyl‐1,2,4‐triazol‐5‐ylidene (L^Ph) under mild conditions and in the presence of MeOH or water give [ReOX₂(Y)(PPh₃)(L^Ph)] complexes (X = Cl, Br; Y = OMe, OH). Attempted reactions of the carbene precursor 5‐methoxy‐1,3,4‐triphenyl‐4,5‐dihydro‐1H‐1,2,4‐triazole ( 1 ) with [ReOCl₃(PPh₃)₂] or [NBu₄][ReOCl₄] in boiling xylene resulted in protonation of the intermediately formed carbene and decomposition products such as [HL^Ph][ReOCl₄(OPPh₃)], [HL^Ph][ReOCl₄(OH₂)] or [HL^Ph][ReO₄] were isolated. The neutral [ReOX₂(Y)(PPh₃)(HL^Ph)] complexes are purple, airstable solids. The bulky NHC ligands coordinate monodentate and in cis‐position to PPh₃. The relatively long Re–C bond lengths of approximate 2.1Å indicate metal‐carbon single bonds.     

Syntheses,structures and characterization of isomorphous CoII and NiII coordination polymers based on 2‐[(1H‐imidazol‐1‐yl)methyl]‐6‐methyl‐1H‐benzimidazole and benzene‐1,4‐dicarboxylate

Careful choice of the organic ligands is one of the most important parameters in the rational design and synthesis of coordination polymers. Aromatic polycarboxylates have been widely used in the preparation of metal–organic polymers since they can utilize various coordination modes to form diverse structures and can act as hydrogen‐bond acceptors and donors in the assembly of supramolecular structures. Nitrogen‐heterocyclic organic compounds have also been used extensively as ligands for the construction of polymers with interesting structures. In the polymers catena‐poly[[[diaquabis{2‐[(1H‐imidazol‐1‐yl)methyl]‐6‐methyl‐1H‐benzimidazole‐κN ³}cobalt(II)]‐μ₂‐benzene‐1,4‐dicarboxylato‐κ²O ¹:O ⁴] dihydrate], {[Co(C₈H₄O₄)(C₁₂H₁₁N₄)₂(H₂O)₂]·2H₂O}_n , (I), and catena‐poly[[[diaquabis{2‐[(1H‐imidazol‐1‐yl)methyl]‐6‐methyl‐1H‐benzimidazole‐κN ³}nickel(II)]‐μ₂‐benzene‐1,4‐dicarboxylato‐κ²O ¹:O ⁴] dihydrate], {[Ni(C₈H₄O₄)(C₁₂H₁₁N₄)₂(H₂O)₂]·2H₂O}_n , (II), the Co^II or Ni^II ion lies on an inversion centre and exhibits a slightly distorted octahedral coordination geometry, coordinated by two N atoms from two imidazole rings and four O atoms from two monodentate carboxylate groups and two water molecules. The dicarboxylate ligands bridge metal ions forming a polymeric chain. The 2‐[(1H‐imidazol‐1‐yl)methyl]‐6‐methyl‐1H‐benzimidazole ligands coordinate to the Co^II or Ni^II centres in monodentate modes through an imidazole N atom and are pendant on opposite sides of the main chain. The two structures are isomorphous. In the crystal, the one‐dimensional chains are further connected through O—H…O, O—H…N and N—H…O hydrogen bonds, leading to a three‐dimensional supramolecular architecture. In addition, the IR spectroscopic properties, PXRD patterns, thermogravimetric behaviours and fluorescence properties of both polymers have been investigated.     

Synthesis,X‐ray characterization and density functional theory studies of N6‐benzyl‐N6‐methyladenine–M(II) complexes (M = Zn,Cd): The prominent role of π–π, C–H···π and anion–π interactions

We report the synthesis and X‐ray characterization of the N⁶‐benzyl‐N⁶‐methyladenine ligand (L) and three metal complexes, namely [Zn(HL)Cl₃]·H₂O ( 1 ), [Cd(HL)₂Cl₄] ( 2 ) and [H₂L]₂[Cd₃(μ‐L)₂(μ‐Cl)₄Cl₆]·3H₂O ( 3 ). Complex 1 consists of the 7H‐adenine tautomer protonated at N3 and coordinated to a tetrahedral Zn(II) metal centre through N9. The octahedral Cd(II) in complex 2 is N⁹‐coordinated to two N⁶‐benzyl‐N⁶‐methyladeninium ligands (7H‐tautomer protonated at N3) that occupy apical positions and four chlorido ligands form the basal plane. Compound 3 corresponds to a trinuclear Cd(II) complex, where the central Cd atom is six‐coordinated to two bridging μ‐L and four bridging μ‐Cl ligands. The other two Cd atoms are six‐coordinated to three terminal chlorido ligands, to two bridging μ‐Cl ligands and to the bridging μ‐L through N3. Essentially, the coordination patterns, degree of protonation and tautomeric forms of the nucleobase dominate the solid‐state architectures of 1 – 3 . Additionally, the hydrogen‐bonding interactions produced by the endocyclic N atoms and NH groups stabilize high‐dimensional‐order supramolecular assemblies. Moreover, energetically strong anion–π and lone pair (lp)–π interactions are important in constructing the final solid‐state architectures in 1 – 3 . We have studied the non‐covalent interactions energetically using density functional theory calculations and rationalized the interactions using molecular electrostatic potential surfaces and Bader's theory of atoms in molecules. We have particularly analysed cooperative lp–π and anion–π interactions in 1 and π⁺–π⁺ interactions in 3 .     

A new two‐dimensional managnese(II) coordination polymer constructed by 2,2′‐(1,2‐phenylene)bis(1H‐imidazole‐4,5‐dicarboxylate)

In recent years, N‐heterocyclic carboxylate ligands have attracted much interest in the preparation of new coordination polymers since they contain N‐atom donors, as well as O‐atom donors, and have a rich variety of coordination modes which can lead to polymers with intriguing structures and interesting properties. A new two‐dimensional coordination polymer, namely poly[[μ₃‐2,2′‐(1,2‐phenylene)bis(4‐carboxy‐1H‐imidazole‐5‐carboxylato)‐κ⁶O⁴,N³,N^3′,O^4′:O⁵:O^5′]manganese(II)], [Mn(C₁₆H₈N₄O₈)]_n or [Mn(H₄Phbidc)]_n, has been synthesized by the reaction of Mn(OAc)₂·4H₂O (OAc is acetate) with 2,2′‐(1,2‐phenylene)bis(1H‐imidazole‐4,5‐dicarboxylic acid) (H₆Phbidc) under solvothermal conditions. In the polymer, each Mn^II ion is six‐coordinated by two N atoms from one H₄Phbidc²⁻ ligand and by four O atoms from three H₄Phbidc²⁻ ligands, forming a significantly distorted octahedral MnN₂O₄ coordination geometry. The Mn^II ions are linked by hexadentate H₄Phbidc²⁻ ligands, leading to a two‐dimensional structure parallel to the ac plane. In the crystal, adjacent layers are further connected by N—H…O hydrogen bonds, forming a three‐dimensional structure in the solid state.     

2‐Amino‐5‐(2‐pyridyl)‐thiadiazole as Bidentate Ligand

The amino substituted bidentate chelating ligand 2‐amino‐5‐(2‐pyridyl)‐1,3,4‐thiadiazole (H₂ L ) was used to prepare 3:1‐type coordination compounds of iron(II), cobalt(II) and nickel(II). In the iron(II) perchlorate complex [Fe^II(H₂ L )₃](ClO₄)₂·0.6MeOH·0.9H₂O a 1:1 mixture of mer and fac isomers is present whereas [Fe^II(H₂ L )₃](BF₄)₂·MeOH·H₂O, [Co^II(H₂ L )₃](ClO₄)₂·2H₂O and [Ni^II(H₂ L )₃](ClO₄)₂·MeOH·H₂O feature merely mer derivatives. Moessbauer spectroscopy and variable temperature magnetic measurements revealed the [Fe^II(H₂ L )₃]²⁺ complex core to exist in the low‐spin state, whereas the [Co^II(H₂ L )₃]²⁺ complex core resides in its high‐spin state, even at very low temperatures.     

Synthesis,Structural Characterization,and Antimicrobial Activities of Mn(II), Co(II), Ni(II), Cu(II) and Zn(II) Complexes of Triazole‐based Azodyes

The synthesis and characterization of new transition metal complexes of Mn(II), Co(II), Ni(II), Cu(II) and Zn(II) with 3‐(2‐hydroxynaph‐1‐ylazo)‐1,2,4‐triazole ( HL¹ ) and 3‐(2‐hydroxy‐3‐carboxynaph‐1‐ylazo)‐1,2,4‐triazole ( HL² ) have been carried out. Their structures were confirmed by elemental analyses, thermal analyses, spectral and magnetic data. The IR and ¹H NMR spectra indicated that HL¹ and HL² coordinated to the metal ions as bidentate monobasic ligands via the hydroxyl O and azo N atoms. The UV‐Vis, ESR spectra and magnetic moment data revealed the formation of octahedral complexes [Mn L¹ (AcO)(H₂O)₃] ( 1 ), [Co L¹ (AcO)(H₂O)₃]·H₂O ( 2 ), [Mn L² (AcO)(H₂O)₃] ( 6 ) and [Co L² (AcO)(H₂O)₃] ( 7 ), [Ni L¹ (AcO)(H₂O)] ( 3 ), [Zn L¹ (AcO)(H₂O)]·H₂O ( 5 ), [Ni L² (AcO)(H₂O)] ( 8 ), [Zn L² (AcO)(H₂O)]·10H₂O ( 10 ) have tetrahedral geometry, whereas [Cu L¹ (AcO)(H₂O)₂] ( 4 ) and [Cu L² (AcO)(H₂O)₂]·5H₂O ( 9 ) have square pyramidal geometry.. The mass spectra of the complexes under EI‐con‐ ditions showed the highest peaks corresponding to their molecular weights, based on the atomic weights of ⁵⁵Mn, ⁵⁹Co, ⁵⁸Ni, ⁶³Cu and ⁶⁴Zn isotopes; besides, other peaks containing other isotopes distribution of the metal. Kinetic and thermodynamic parameters of the thermal decomposition stages were computed from the thermal data using Coats‐Redfern method. HL² and complexes 6 – 10 were found to have moderate antimicrobial activities against Staphylococcus aureus (gram positive), Escherichia coli (gram negative) and Salmonella sp bacteria, and antifungal activity against Fusarium oxysporum, Aspergillus niger and Candida albicans. Also, in most cases, metallation increased the activity compared with the free ligand.     

Synthesis and Crystal Structures of Bis(1‐{(E)‐2‐pyridinylmethylidene}‐semicarbazone)iron(II) and ‐copper(II) Diperchlorate Monohydrates

The pyridine‐2‐carbaldehyde semicarbazone ligand (HL) reacts with iron(II) and copper(II) perchlorates in boiling ethanol to yield red‐violet [Fe^II(HL)₂](ClO₄)₂·H₂O ( 1 ) and light‐green crystals [Cu^II(HL)₂](ClO₄)₂·H₂O ( 2 ). The crystals are triclinic with the metal ions in an octahedral environment, coordinated to two nitrogen and one oxygen‐donor atom from HL. Electronic, magnetic and electrochemical properties are presented as well.