[Mn12O12(O2CMe)12(NO3)4(H2O)4]: facile synthesis of a new type of Mn12 complex

The title dodecanuclear Mn complex, namely dodeca‐μ₂‐acetato‐κ²⁴O:O′‐tetraaquatetra‐μ₂‐nitrato‐κ⁸O:O′‐tetra‐μ₄‐oxido‐octa‐μ₃‐oxido‐tetramanganese(IV)octamanganese(III) nitromethane tetrasolvate, [Mn₁₂(CH₃COO)₁₂(NO₃)₄O₁₂(H₂O)₄]·4CH₃NO₂, was synthesized by the reaction of Mn²⁺ and Ce⁴⁺ sources in nitromethane with an excess of acetic acid. This compound is distinct from the previously known single‐molecule magnet [Mn₁₂O₁₂(O₂CMe)₁₆(H₂O)₄], synthesized by Lis [Acta Cryst. (1980), B 36 , 2042–2044]. It is the first Mn₁₂‐type molecule containing nitrate ligands to be directly synthesized without the use of a preformed cluster. Additionally, this molecule is distinct from all other known Mn₁₂ complexes due to intermolecular hydrogen bonds between the nitrate and water ligands, which give rise to a three‐dimensional network. The complex is compared to other known Mn₁₂ molecules in terms of its structural parameters and symmetry.     

Two new soluble iron–oxo complexes: [Fe2(μ‐O)(μ‐O2CCF3)2(O2CCF3)2(C10H8N2)2] and [Fe4(μ3‐O)2(μ‐O2CCF3)6(O2CCF3)2(C10H8N2)2]·CF3CO2H

Two new iron–oxo clusters, viz. di‐μ‐tri­fluoro­acetato‐μ‐oxo‐bis­[(2,2′‐bi­pyridine‐κ²N,N′)(tri­fluoro­acetato‐κO)­iron(III)], [Fe₂O(CF₃CO₂)₄(C₁₀H₈N₂)₂], and bis(2,2′‐bi­pyridine)­di‐μ₃‐oxo‐hexa‐μ‐tri­fluoro­acetato‐bis­(tri­fluoro­acetato)­tetrairon(III) tri­fluoro­acetic acid solvate, [Fe₄O₂(CF₃CO₂)₈(C₁₀H₈N₂)₂]·CF₃CO₂H, contain dinuclear and tetranuclear Fe^III cores, respectively. The Fe^III atoms are in distorted octahedral environments in both compounds and are linked by oxide and tri­fluoro­acetate ions. The tri­fluoro­acetate ions are either bridging (bidentate) or coordinated to the Fe^III atoms via one O atom only. The fluorinated peripheries enhance the solubility of these compounds. Formal charges for all the Fe centers were assigned by summing valences of the chemical bonds to the Fe^III atom.     

A novel octanuclear nickel(II)–molybdenum(VI) heterometallic cluster based on the salicylhydroxamate ligand

Salicylhydroxamic acid (H₃shi) is known for its strong coordination ability and multiple coordination modes, and can easily coordinate to metal cations to form compounds with five‐ or six‐membered rings, as well as mono‐, di‐ and multinuclear compounds with interesting structures having potential applications in organic chemistry, coordination chemistry, and the materials and biological sciences. A novel octanuclear nickel(II)–molybdenum(VI) heterometallic cluster based on the salicylhydroxamate ligand, namely di‐μ₃‐acetato‐di‐μ₂‐acetato‐di‐μ₃‐hydroxido‐di‐μ₃‐oxido‐tetraoxidooctakis(pyridine‐κN)bis(μ₅‐salicylhydroxamato)hexanickel(II)dimolybdenum(VI) monohydrate, [Mo₂Ni₆(C₇H₄NO₃)₂(C₂H₃O₂)₄O₅(OH)₂(C₅H₅N)₈]·H₂O, (I), was synthesized by the reaction of sodium molybdate, nickel acetate and salicylhydroxamic acid in a dimethylformamide/pyridine/methanol solution at room temperature. The salicylhydroxamate(3−) (shi³⁻), acetate and oxide ligands adopt complicated coordination modes and link six Ni^II and two Mo^VI cations into the octanuclear heterometallic cluster. All of the metal cations exhibit octahedral coordination geometries and are connected to each other through the sharing of corners, edges or planes. The heterometallic clusters are further connected to form two‐dimensional supramolecular layers through weak C—H…O hydrogen bonds. Studies of the magnetic properties of the title compound reveal antiferromagnetic interactions between the Ni^II cations.     

A polymeric cobalt(II) complex derived from citric acid (H4cit) and 2,6‐diaminopurine (dap): {[Co4(cit)2(dap)4(H2O)4]·6.35H2O}n

Poly[[tetraaquadi‐μ₄‐citrato‐tetrakis(2,6‐diaminopurine)tetracobalt(II)] 6.35‐hydrate], {[Co₄(C₆H₄O₇)₂(C₅H₆N₆)₄(H₂O)₄]·6.35H₂O}_n, presents three different types of Co^II cations in the asymmetric unit, two of them lying on symmetry elements (one on an inversion centre and the other on a twofold axis). The main fragment is further composed of one fully deprotonated citrate (cit) tetraanion, two 2,6‐diaminopurine (dap) molecules and two aqua ligands. The structure is completed by a mixture of fully occupied and disordered solvent water molecules. The two independent dap ligands are neutral and the cit tetraanion provides for charge balance, compensating the 4+ cationic charge. There are two well defined coordination geometries in the structure. The simplest is mononuclear, with the Co^II cation arranged in a regular centrosymmetric octahedral array, coordinated by two aqua ligands, two dap ligands and two O atoms from the β‐carboxylate groups of the bridging cit tetraanions. The second, more complex, group is trinuclear, bisected by a twofold axis, with the metal centres coordinated by two cit tetraanions through their α‐ and β‐carboxylate and α‐hydroxy groups, and by two dap ligands bridging through one of their pyridine and one of their imidazole N atoms. The resulting coordination geometry around each metal centre is distorted octahedral. Both groups are linked alternately to each other, defining parallel chains along [201], laterally interleaved and well connected via hydrogen bonding to form a strongly coupled three‐dimensional network. The compound presents a novel μ₄‐κ⁵O:O,O′:O′,O′′,O′′′:O′′′′ mode of coordination of the cit tetraanion.     

A one‐dimensional coordination polymer with a capped [Cu4O4] cubane core assembled from 2‐(hydroxymethyl)pyridine

The one‐dimensional coordination polymer catena‐poly[[[di‐μ₂‐acetato‐tetrakis[μ₃‐(pyridin‐2‐yl)methanolato]tetracopper(II)]‐di‐μ₂‐diacetamidato] acetonitrile monosolvate], {[Cu₄(C₆H₆NO)₄(CH₃COO)₂(C₂N₃)₂]·CH₃CN}_n, has been prepared from the direct reaction of 2‐(hydroxymethyl)pyridine with Cu(OAc)₂·H₂O (OAc⁻ is acetate) in a methanol–acetonitrile mixture. The four Cu centres are bridged by four O atoms from discrete (pyridin‐2‐yl)methanolate ligands and two acetate groups, forming a capped [Cu₄O₄] cubane core. Each core is doubly bridged to each of two adjacent cores by [N(CN)₂]⁻ anions, resulting in one‐dimensional chains. The magnetic properties of the complex were also studied.     

A candidate for a single‐chain magnet: [Mn3(OAc)6(py)2(H2O)2]n (OAc is acetate and py is pyridine)

The title complex, catena‐poly[di‐μ₃‐acetato‐κ⁶O:O:O′‐tetra‐μ₂‐acetato‐κ⁴O:O;κ⁴O:O′‐diaquabis(pyridine‐κN)trimanganese(II)], [Mn₃(CH₃COO)₆(C₆H₅N)₂(H₂O)₂]_n, is a true one‐dimensional coordination polymer, in which the Mn^II centres form a zigzag chain along [010]. The asymmetric unit contains two metal centres, one of which (Mn1) lies on an inversion centre, while the other (Mn2) is placed close to an inversion centre on a general position. Since all the acetates behave as bridging ligands, although with different μ₂‐ and μ₃‐coordination modes, a one‐dimensional polymeric structure is formed, based on trinuclear repeat units (Mn1...Mn2...Mn2′), in which the Mn2 and Mn2′ sites are related by an inversion centre. Within this monomeric block, the metal–metal separations are Mn1...Mn2 = 3.36180 (18) Å and Mn2...Mn2′ = 4.4804 (3) Å. Cation Mn1, located on an inversion centre, displays an [MnO₆] coordination sphere, while Mn2, on a general position, has a slightly stronger [MnO₅N] ligand field, as the sixth coordination site is occupied by a pyridine molecule. Both centres approximate an octahedral ligand field. The chains are parallel in the crystal structure and interact via hydrogen bonds involving coordinated water molecules. However, the shortest metal–metal separation between two chains [5.3752 (3) Å] is large compared with the intrachain interactions. These structural features are compatible with a single‐chain magnet behaviour, as confirmed by preliminary magnetic studies.     

[CoII4MoV12O28(OH)12(H2O)12]·12H2O: facilitating single‐crystal growth by deuteration

The structure of the neutral heterometal oxide cluster dodecaaqua‐di‐μ₃‐hydroxido‐deca‐μ₂‐hydroxido‐octacosaoxidotetracobalt(II)dodecamolybdenum(V) dodecahydrate, [Mo₁₂O₂₈(μ₂‐OH)₁₀(μ₃‐OH)₂{Co(H₂O)₃}₄], is virtually identical to the previously reported Ni^II analogue [Mo₁₂O₂₈(μ₂‐OH)₁₀(μ₃‐OH)₂{Ni^II(H₂O)₃}₄] [Müller, Beugholt, Kögerler, Bögge, Budko & Luban (2000). Inorg. Chem. 39 , 5176–5177], the first molecular magnet to exhibit signs of magnetostriction. The formation kinetics of the neutral cluster species, which is insoluble in water, can be significantly slowed by the use of deuterated reactants in order to grow single crystals of sufficient size for single‐crystal X‐ray diffraction studies using standard diffractometers. One half of the main cluster and six solvent water molecules constitute the asymmetric unit. The main cluster is located on a mirror plane.     

A neodymium(III)–ammonium complex involving oxalate and carbonate ligands: (NH4)2[Nd2(C2O4)3(CO3)(H2O)]·H2O

The title compound, di­ammonium aqua‐μ‐carbonato‐tri‐μ‐­oxalato‐dineodymium(III) hydrate, (NH₄)₂[Nd₂(CO₃)(C₂O₄)₃(H₂O)]·H₂O, involving the two ligands oxalate and carbonate, has been prepared hydro­thermally as single crystals. The Nd atoms form a tetranuclear unit across the inversion centre at (,,). Starting from this tetranuclear unit, the oxalate ligands serve to develop a three‐dimensional network. The carbonate group acts as a bis‐chelating ligand to two Nd atoms, and is monodentate to a third Nd atom. The oxalate groups are all bis‐chelating. The two independent Nd atoms are ninefold coordinated and the coordination polyhedron of these atoms is a distorted monocapped antiprism.     

Two oxo complexes with tetra­nuclear [Fe4(μ3‐O)2]8+ and trinuclear [Fe3(μ3‐O)]7+ units

Two new oxo complexes, namely hexa‐μ₂‐acetato‐acetato­aquabis­(di‐3‐pyridylamine)di‐μ₃‐oxo‐tetra­iron(III) chloride mono­hydrate ethanol 1.25‐solvate, [Fe₄(C₂H₃O₂)₇O₂(C₁₀H₉N₃)₂(H₂O)]Cl·1.25C₂H₆O·H₂O, (I), containing a tetra­nuclear [Fe₄(μ₃‐O)₂]⁸⁺ unit, and 2‐methyl­imidazolium hexa‐μ₂‐acetato‐acetatodiaqua‐μ₃‐oxo‐triiron(III) chloride dihydrate, (C₄H₇N₂)[Fe₃(C₂H₃O₂)₇O(H₂O)₂]Cl·2H₂O, (II), with a trinuclear [Fe₃(μ₃‐O)]⁷⁺ unit, are presented. Both structures are formed by two well differentiated entities, viz. a compact isolated cluster composed of Fe^III ions coordinated to O²⁻ and CH₃CO₂⁻ anions, and an external group formed by a central Cl⁻ ion surrounded by different solvent groups to which the anion is bound through hydrogen bonding. In the case of (I), charge balance cannot be achieved within the groups, so the structure is macroscopically ionic; in the case of (II), in contrast, each group is locally neutral owing to the inter­nal compensation of charges. The trinuclear complex crystallizes with the metal cluster, chloride anion and 2‐methyl­imidazolium cation bisected by a crystallographic mirror plane.     

Ag(I)配位聚合物[Ag2(bpp)2(H2O)]·pydc·7H2O的合成、表征及性质研究

水热合成了基于吡啶-3,5-二羧酸(H2pydc)的含Ag(I)配位聚合物 [Ag2(bpp)2(H2O)]·pydc·7H2O (1) (其中bpp = 1,3-双(4-吡啶)丙烷)。X射线单晶结构分析表明,在一维化合物1中,发现了包含(H2O)12水簇单元的二维氢键层状结构。有趣的是,在该二维层中, 每个pydc2-阴离子作为“桥”连接了两个(H2O)12单元和两个自由水分子。另外,对化合物1的荧光、热重、粉末衍射等也进行了研究和讨论。     

Synthesis and Crystal Structures of Two Complexes [Mn2(L)2(H2bta)2(H2O)]n and[Cu2(L)(H2bta)0.5(H2O)]n

Two new complexes, [Mn₂(L)₂(H₂bta)₂(H₂O)]_n ( 1 ) and [Cu₂(L)(H₂bta)_0.5(H₂O)]_n ( 2 ) (H₄bta=1,2,4,5‐benzene‐tetracarboxylic acid, L=imidazo[4,5‐f][1,10]phenathroline) were prepared under hydrothermal conditions and their structures determined by single‐crystal X‐ray diffration. The X‐ray diffraction reveals that complex 1 , consisting of two crystallographically independent fragments A1 and A2, displays an interesting 3D supramolecular network constructed with ABAB sequence through hydrogen bonding interactions. In complex 2 , the copper atoms connected by the H₂bta^2? ligands, the chains also are assembled into a 3D honeycomb configuration network formed by moleculars and aromatic π‐π stacking interactions.     

Disorder effects in Mn12–acetate at 83 K

The structure of hexadeca‐μ‐acetato‐tetra­aqua­dodeca‐μ₃‐oxo‐dodecamanganese bis(acetic acid) tetrahydrate, [Mn₁₂O₁₂(CH₃COO)₁₆(H₂O)₄]·2CH₃COOH·4H₂O, known as Mn₁₂–acetate, has been determined at 83 (2) K by X‐ray diffraction methods. The fourfold (S₄) molecular symmetry is disrupted by a strong hydrogen‐bonding interaction with the disordered acetic acid mol­ecule of solvation, which displaces one of the acetate ligands in the cluster. Up to six Mn₁₂ isomers are potentially present in the crystal lattice, which differ in the number and arrangement of hydrogen‐bonded acetic acid mol­ecules. These results considerably improve the structural information available on this molecular nanomagnet, which was first synthesized and characterized by Lis [Acta Cryst. (1980), B 36 , 2042–2046].     

Bis(5‐aminotetrazole‐1‐acetato‐κO)tetraaquacobalt(II) and catena‐poly[[cadmium(II)]‐bis(μ‐5‐aminotetrazole‐1‐acetato‐κ3N4:O,O′)]

The Co^II atom in bis(5‐aminotetrazole‐1‐acetato)tetraaquacobalt(II), [Co(C₃H₄N₅O₂)₂(H₂O)₄], (I), is octahedrally coordinated by six O atoms from two 5‐aminotetrazole‐1‐acetate (atza) ligands and four water molecules. The molecule has a crystallographic centre of symmetry located at the Co^II atom. The molecules of (I) are interlinked by hydrogen‐bond interactions, forming a two‐dimensional supramolecular network structure in the ac plane. The Cd^II atom in catena‐poly[[cadmium(II)]‐bis(μ‐5‐aminotetrazole‐1‐acetato], [Cd(C₃H₄N₅O₂)₂]_n, (II), lies on a twofold axis and is coordinated by two N atoms and four O atoms from four atza ligands to form a distorted octahedral coordination environment. The Cd^II centres are connected through tridentate atza bridging ligands to form a two‐dimensional layered structure extending along the ab plane, which is further linked into a three‐dimensional structure through hydrogen‐bond interactions.     

Double complexes [Co(NH3)5(H2O)]2[Zr3F18]·6H2O and [Co(NH3)6]2[Zr3F18]·6H2O

The structures of orthorhombic bis[pentaammineaquacobalt(III)] tetra‐μ₂‐fluorido‐tetradecafluoridotrizirconium(IV) hexahydrate (space group Ibam), [Co(NH₃)₅(H₂O)]₂[Zr₃F₁₈]·6H₂O, (I), and bis[hexaamminecobalt(III)] tetra‐μ₂‐fluorido‐tetradecafluoridotrizirconium(IV) hexahydrate (space group Pnna), [Co(NH₃)₆]₂[Zr₃F₁₈]·6H₂O, (II), consist of complex [Co(NH₃)_x(H₂O)_y]³⁺ cations with either m [in (I)] or and 2 [in (II)] symmetry, [Zr₃F₁₈]⁶⁻ anionic chains located on sites with 222 [in (I)] or 2 [in (II)] symmetry, and water molecules.     

Rb(GaPO4)2(OH)(H2O)·H2O: a hydrated rubidium gallium phosphate analogue of GaPO4·2H2O and leucophosphite

Crystals of the title hydrated rubidium gallium phosphate, rubidium aqua‐μ₃‐hydroxo‐di‐μ‐phosphato‐digallium hydrate, were synthesized hydro­thermally at 453 K under autogenous pressure. The solid crystallizes in the monoclinic system and its structure was determined from single‐crystal X‐ray diffraction analysis. It is similar to dihydrated gallium phosphate, GaPO₄·2H₂O, which is isostructural with the mineral leucophosphite. The structure is built up from a three‐dimensional anionic framework composed of corner‐linked octameric Ga₄(PO₄)₄(OH)₂(H₂O)₂ units. The Ga atom is in an octahedral coordination. Connection of the Ga₄P₄ species generates eight‐ring channels, in which are encapsulated the Rb⁺ cations and water mol­ecules.     

[Cr8(PhCO2)16O4]·4CH3CN·2H2O: structural origin of magnetic anisotropy in a molecular spin cluster

The Cr₄O₄ hetero‐cubane‐centered octachromium(III) cluster [Cr₈(PhCO₂)₁₆O₄] crystallizes from fluorobenzene–acetonitrile as dodeca‐μ₂‐benzoato‐tetrabenzoatotetra‐μ₄‐oxido‐octachromium(III) acetonitrile tetrasolvate dihydrate, [Cr₈(C₇H₅O₂)₁₆O₄]·4C₂H₃N·2H₂O, (I). Crystals produced by this method are significantly more stable than the originally published dichloromethane pentasolvate, [Cr₈(PhCO₂)₁₆O₄]·5CH₂Cl₂ [Atkinson et al. (1999). Chem. Commun. pp. 285–286], leading to a significantly higher quality structure and allowing the production of large quantities of high‐quality nondeuterated and deuterated material suitable for inelastic neutron scattering (INS) measurements. Compound (I) reveals a higher symmetry structure in which the cluster sits on a twofold rotation axis, and is based on an asymmetric unit containing four crystallographically independent Cr positions, two oxide ligands, eight benzoate ligands, two acetonitrile solvent molecules and one disordered water molecule. All the Cr atoms are six‐coordinate, with an octahedral geometry for the inner cubane and a more highly distorted coordination environment in the outer positions. Despite the higher symmetry, the coordination geometries observed in (I) are largely similar to the dichloromethane pentasolvate structure, indicating that crystal‐packing effects have little influence on the molecular structure of [Cr₈(PhCO₂)₁₆O₄]. Close structural analysis reveals that the high magnetic anisotropy observed in the INS measurements is a consequence of the distorted coordination geometry of the four outer Cr atoms.     

Synthesis and Crystal Structure of the Binuclear Complex [Pr2(C10H8N2O4)2(C10H9N2O4)2(H2O)4]·3H2O·C6H6

The binuclear praseodymium(III) complex with N‐(1‐carboxyethylidene)‐salicylhydrazide (C₁₀H₁₀N₂O₄, H₂L) was prepared in H₂O‐C₂H₅OH mixed solution, and the crystal structure of [Pr₂L₂(HL)₂(H₂O)₄]·3H₂O·C₆H₆ was determined by X‐ray single crystal diffraction. The crystal complex crystallizes in the triclinic system with space group P‐1, and in the structure each Pr atom is 9‐coordinated by carboxyl O and acyl O and azomethine N atoms of two tridentate ligands to form two stable five‐membered rings sharing one side in keto‐mode and two water molecules. The coordination polyhedron around Pr³⁺ was described as a monocapped square antiprism geometry. In an individual molecule, four tridentate ligands were coordinated by two negative univalent (HL) and two bivalent forms (L) respectively. Two negative univalent ligands were coordinated via μ₂‐bridging mode.     

A novel (4,6)‐connected double‐layered BaII coordination polymer based on the flexible tricarboxylate ligand 2,2′,2′′‐[1,3,5‐triazine‐2,4,6‐triyltris(sulfanediyl)]triacetic acid

In the title compound, poly[[triaqua{μ₄‐2‐[4,6‐bis(carboxymethylsulfanyl)‐1,3,5‐triazin‐2‐ylsulfanyl]acetato}{μ₂‐2‐[4,6‐bis(carboxymethylsulfanyl)‐1,3,5‐triazin‐2‐ylsulfanyl]acetato}barium(II)] monohydrate], {[Ba(C₉H₈N₃O₆S₃)₂(H₂O)₃]·H₂O}_n, each Ba^II atom is nine‐coordinated by six O atoms from carboxylate groups of four different 2‐[4,6‐bis(carboxymethylsulfanyl)‐1,3,5‐triazin‐2‐ylsulfanyl]acetate ligands and three O atoms from water molecules. The triazine ligand is partially deprotonated, as verified by intermolecular hydrogen‐bonding parameters, and adopts μ₂‐η¹:η¹ and μ₄‐η¹:η¹:η² coordination modes to connect the Ba^II centres, forming a novel double‐layered structure. Topological analysis indicates that the whole structure is a novel (4,6)‐connected net, considering the ligands and Ba^II centres as four‐ and six‐connected nodes, respectively.     

Li+ cation coordination in [Li2(CF3SO3)2(diglyme)] and [Li3(C2F3O2)3(diglyme)]

The title compounds, poly­[[[bis(2‐methoxy­ethyl) ether]­lithium(I)]‐di‐μ₃‐tri­fluoro­methanesulfonato‐lithium(I)], [Li₂(CF₃SO₃)₂(C₆H₁₄O₃)]_n, and poly­[[[bis(2‐methoxy­ethyl) ether]­lithium(I)]‐di‐μ₃‐tri­fluoro­acetato‐dilithium(I)‐μ₃‐tri­fluoro­acetato], [Li₃(C₂F₃O₂)₃(C₆H₁₄O₃)]_n, consist of one‐dimensional polymer chains. Both structures contain five‐coordinate Li⁺ cations coordinated by a tridentate diglyme [bis(2‐methoxy­ethyl) ether] mol­ecule and two O atoms, each from separate anions. In both structures, the [Li(diglyme)X₂]^? (X is CF₃SO₃ or CF₃CO₂) fragments are further connected by other Li⁺ cations and anions, creating one‐dimensional chains. These connecting Li⁺ cations are coordinated by four separate anions in both compounds. The CF₃SO₃^? and CF₃CO₂^? anions, however, adopt different forms of cation coordination, resulting in differences in the connectivity of the structures and solvate stoichiometries.     

Synthesis and Characterization of a Novel Binuclear Cobalt(II) Complex with Discrete Water Clusters (H2O)8

A new octameric water cluster was observed in the complex Co₂(dptc)(bipy)₂(H₂O)₆ · 4H₂O ( 1 ) (H₄dptc = diphenyl‐3,3′,4,4′‐tetracarboxylic acid; bipy = 2,2′‐bipyridine), which was characterized by single‐crystal X‐ray diffraction, elemental analysis and IR spectroscopy. The centrosymmetric octamer consists of a water hexamer in the chair form and two water molecules and brings to light a novel mode of the cooperative association of water molecules. Those complex units are connected into a 2D infinite layer framework through hydrogen bonding. Consequently, the 2D layers are further aggregated by hydrogen bonding with octameric subunits and π ··· π stacking interactions to form a 3D supramolecular architecture.