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.     

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.     

Di‐μ‐sulfito‐bis­[(4,4′‐di­methyl‐2,2′‐bi­pyridine)­zinc(II)] dihydrate and poly­[[aqua(1,10‐phenanthroline)­zinc(II)]‐μ3‐sulfito‐zinc(II)‐μ3‐sulfito]

Two different zinc sulfite compounds have been prepared through the decomposition of pyrosulfite–­di­thionite ions in aqueous solution, viz. a dimeric complex, di‐μ‐sulfito‐κ³O,O′:O′′;κ³O:O′,O′′‐bis­[(4,4′‐di­methyl‐2,2′‐bi­pyridine‐κ²N,N′)­zinc(II)] dihydrate, [Zn₂(SO₃)₂(C₁₂H₁₂N₂)₂]·2H₂O, (I), which was solved and refined from a twinned sample, and an extended polymer, poly­[[aqua(1,10‐phenanthroline‐κ²N,N′)­zinc(II)]‐μ₃‐sulfito‐κ²O:O′:O′′‐zinc(II)‐μ₃‐sulfito‐κ³O:O:O′], [Zn₂(SO₃)₂(C₁₂H₁₀N₂)(H₂O)]_n, (II). In (I), the dinuclear Zn^II complex has a center of symmetry. The cation is five‐coordinate in a square‐pyramidal arrangement, the anion fulfilling a bridging chelating role. Compound (II) comprises two different zinc units, one being five‐coordinate (square pyramidal) and the other four‐coordinate (trigonal pyramidal), and two independent sulfite groups with different binding modes to the cationic centers.     

Synthesis,structure and magnetism of a new ionic pentanuclear iron cluster

A new ionic pentanuclear Fe^III cluster, namely, triethylazanium tetrakis(μ₂‐5‐amino‐1,2,3,4‐tetrazolido)tetrakis(μ₃‐4‐chloro‐2‐{[(1H‐tetrazol‐1‐id‐5‐yl)imino]methyl}phenolato)di‐μ₃‐oxido‐pentairon(III) acetonitrile monosolvate monohydrate, (C₆H₁₆N)[Fe₅(C₈H₄ClN₅O)₄(CH₂N₅)₄O₂]·CH₃CN·H₂O, was synthesized using microvial synthesis methods and characterized by elemental analysis, FT–IR spectroscopy, single‐crystal X‐ray diffraction and thermogravimetric analysis. Magnetic studies reveal that the complex displays dominant antiferromagnetic intracluster interactions between the Fe^III ions through the μ₃‐oxide bridges.     

Dimeric hexakis(4‐methyl­benzoato)­bis(1,10‐phenanthroline)didyspros­ium(III)

The title compound, [Dy₂(C₈H₇O₂)₆(C₁₂H₈N₂)₂], forms binuclear complexes, viz. di‐μ‐4‐methyl­benzoato‐κ⁴O:O′‐bis[bis(4‐methyl­benzoato‐κ²O,O′)(1,10‐phenanthroline‐κ²N,N′)dyspros­ium(III)] tetra‐μ‐4‐methyl­benzoato‐κ⁸O:O′‐bis[(4‐methyl­benzoato‐κ²O,O′)(1,10‐phenanthroline‐κ²N,N′)dyspros­ium(III)]. There are two independent binuclear com­plexes in the asymmetric unit, both of which are centrosymmetric. In one, the Dy^III ions are linked by two bridging 4‐­methyl­benzoate groups, while in the other, the Dy^III ions are linked by four bridging 4‐methyl­benzoate groups. The remaining 4‐methyl­benzoate groups and 1,10‐phenanthroline units coordinate to just one metal ion in bidentate modes.     

Multiple bridging modes in a novel trinuclear titanium 1,3‐dioxypropane compound,Ti3(methyliminodiethanolate)2(1,3‐propanediolate)4

The title compound, bis(2,2′‐methyl­imino­diethano­lato)‐1κ³O,N,O′;3κ³O,N,O′‐di‐μ₃‐propane‐1,3‐diolato‐1:2:3κ⁸O:O,O′:O′‐μ‐propane‐1,3‐diolato‐1:3κ²O:O′‐propane‐1,3‐diolato‐2κ²O,O′‐trititanium(IV), [Ti₃(C₅H₁₁NO₂)₂(C₃H₆O₂)₄], has four 1,3‐propane­diolate ligands binding in three different modes. Two ligands chelate adjacent Ti atoms with normal μ₃‐O bridges, giving typical edge‐sharing of the Ti distorted octahedra, one chelating to the central Ti atom with no μ‐bridging, and the other spanning the cluster, binding only to the outermost Ti atoms. The two methyl­imino­diethano­late ligands each coordinate to the outer Ti atoms via their N and two O atoms. The Ti—O bond lengths range, in a self‐consistent fashion, from 1.816 (2) to 2.082 (2) Å, while the average Ti—N distance is 2.391 (3) Å.     

Construction of (3,8)‐connected three‐dimensional cobalt(II) and copper(II) coordination polymers with 1,3‐bis[(1,2,4‐triazol‐4‐yl)methyl]benzene and benzene‐1,3,5‐tricarboxylate ligands

Coordination polymers (CPs) have been widely studied because of their diverse and adjustable topologies and wide‐ranging applications in luminescence, chemical sensors, magnetism, photocatalysis, gas adsorption and separation. In the present work, two coordination polymers, namely poly[(μ₅‐benzene‐1,3,5‐tricarboxylato‐κ⁶O¹:O^1′:O³:O³:O⁵,O^5′){μ₃‐1,3‐bis[(1,2,4‐triazol‐4‐yl)methyl]benzene‐κ³N:N′:N′′}di‐μ₃‐hydroxido‐dicobalt(II)], [Co₂(C₉H₃O₆)(OH)(C₁₂H₁₂N₆)]_n or [Co₂(btc)(OH)(mtrb)]_n, (1), and poly[[diaquabis(μ₃‐benzene‐1,3,5‐tricarboxylato‐κ³O¹:O³:O⁵)bis{μ₃‐1,3‐bis[(1,2,4‐triazol‐4‐yl)methyl]benzene‐κ³N:N′:N′′}tetra‐μ₃‐hydroxido‐tetracopper(II)] monohydrate], {[Cu₄(C₉H₃O₆)₂(OH)₂(C₁₂H₁₂N₆)₂(H₂O)₂]·H₂O}_n or {[Cu₄(btc)₂(OH)₂(mtrb)₂(H₂O)₂]·H₂O}_n, (2), were synthesized by the hydrothermal method using 1,3‐bis[(1,2,4‐triazol‐4‐yl)methyl]benzene (mtrb) and benzene‐1,3,5‐tricarboxylate (btc^3?). CP (1) exhibits a (3,8)‐coordinated three‐dimensional (3D) network of the 3,8T38 topological type, with a point symbol of {4,5,6}₂{4²·5⁶·6¹⁶·7²·8²}, based on the tetranuclear hydroxide cobalt(II) cluster [Co₄(μ₃‐OH)₂]. CP (2) shows a (3,8)‐coordinated tfz‐d topology, with a point symbol of {4₃}₂{4⁶·6¹⁸·8⁴}, based on the tetranuclear hydroxide copper(II) cluster [Cu₄(μ₃‐OH)₂]. The different (3,8)‐coordinated 3D networks based on tetranuclear hydroxide–metal clusters of (1) and (2) are controlled by the different central metal ions [Co^II for (1) and Cu^II for (2)]. The thermal stabilities and solid‐state optical diffuse‐reflection spectra were measured. The energy band gaps (E_g) obtained for (1) and (2) were 2.72 and 2.29 eV, respectively. CPs (1) and (2) exhibit good photocatalytic degradation of the organic dyes methylene blue (MB) and rhodamine B (RhB) under visible‐light irradiation.     

A helical zinc(II) coordination polymer assembled from 1,3‐bis[(pyridin‐3‐yl)methoxy]benzene and benzene‐1,4‐dicarboxylic acid

In catena‐poly[[aqua[1,3‐bis(pyridine‐3‐ylmethoxy)benzene‐κN]zinc(II)]‐μ₂‐benzene‐1,4‐dicarboxylato‐κ²O¹:O⁴], [Zn(C₈H₄O₄)(C₁₈H₁₆N₂O₂)(H₂O)]_n, each Zn^II centre is tetrahedrally coordinated by two O atoms of bridging carboxylate groups from two benzene‐1,4‐dicarboxylate anions (denoted L²⁻), one O atom from a water molecule and one N atom from a 1,3‐bis[(pyridin‐3‐yl)methoxy]benzene ligand (denoted bpmb). (Aqua)O—H...N hydrogen‐bonding interactions induce the formation of one‐dimensional helical [Zn(L)(bpmb)(H₂O)]_n chains which are interlinked through (aqua)O—H...O hydrogen‐bonding interactions, producing two‐dimensional corrugated sheets.     

Three isomorphous Ln complexes: {[Ln2(bt)6(bno)(H2O)4]·bno}n (bt is but‐2‐enoate and bno is 4,4′‐bipyridyl N,N′‐dioxide), with Ln = Nd,Er and Y

The polymeric title compounds, namely catena‐poly[[[di‐μ‐but‐2‐enoato‐κ³O:O,O′;κ³O,O′:O′‐bis[diaquadibut‐2‐enoato‐κO;κ²O,O′‐neodymium(III)]]‐μ‐4,4′‐bipyridyl N,N′‐dioxide‐κ²O:O′] 4,4′‐bipyridyl N,N′‐dioxide solvate] and the erbium(III) and yttrium(III) analogues, {[Ln₂(C₄H₅O₂)₆(C₁₀H₈N₂O₂)(H₂O)₄]·C₁₀H₈N₂O₂}_n (Ln = Nd, Er and Y), form from [Ln₂(bt)₆(H₂O)₄] dimers (bt is but‐2‐enoate) bridged by 4,4′‐bipyridyl dioxide (bno) spacers into sets of parallel chains; these linear arrays are interconnected by aqua‐mediated hydrogen bonds into broad two‐dimensional structures, which in turn interact with each other though the hydrogen‐bonded bridged bno solvent units. Both independent bno units in the structures are bisected by symmetry centres.     

Three oxo complexes with a tetra­nuclear [Cu4(μ2‐Cl)6(μ4‐O)] unit

The three title compounds, namely 4‐phenyl‐1H‐imidazolium hexa‐μ₂‐chloro‐chloro‐μ₄‐oxo‐tris­(4‐phenyl‐1H‐imidazole‐κN¹)­tetra­copper(II) monohydrate, (C₉H₉N₂)[Cu₄Cl₇O(C₉H₈N₂)₃]·H₂O, hexa‐μ₂‐chloro‐μ₄‐oxo‐tetra­kis­(pyridine N‐oxide‐κO)tetra­copper(II), [Cu₄Cl₆O(C₅H₅NO)₄], and hexa‐μ₂‐chloro‐tetra­kis(2‐methyl‐1H‐imidazole‐κN¹)‐μ₄‐oxo‐tetra­copper(II) methanol trisolvate, [Cu₄Cl₆O(C₄H₆N₂)₄]·3CH₄O, exhibit the same Cu₄OCl₆ framework, where the O atom at the centre of an almost regular tetra­hedron bridges four copper cations at the corners. This group is in turn surrounded by a Cl₆ octa­hedron, leading to a rather globular species. This special arrangement of the Cu^II cations results in a diversity of magnetic behaviours.     

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.     

[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.     

Soft scorpionate coordination at alkali metals

Reported here are the single‐crystal X‐ray structure analyses of bis‐μ‐methanol‐κ⁴O:O‐bis{[hydrotris(3‐phenyl‐2‐sulfanylidene‐2,3‐dihydro‐1H‐1,3‐imidazol‐1‐yl)borato‐κ³H,S,S′](methanol‐κO)sodium(I)}, [Na₂(C₂₇H₂₂BN₆S₃)₂(CH₄O)₄] (NaTm^Ph), bis‐μ‐methanol‐κ⁴O:O‐bis{[hydrotris(3‐isopropyl‐2‐sulfanylidene‐2,3‐dihydro‐1H‐1,3‐imidazol‐1‐yl)borato‐κ³H,S,S′](methanol‐κO)sodium(I)}–diethyl ether–methanol (1/0.3333/0.0833), [Na₂(C₁₈H₂₈BN₆S₃)₂(CH₄O)₄]·0.3333C₄H₁₀O·0.0833CH₃OH (NaTm^iPr), and a novel anhydrous form of sodium hydrotris(methylthioimidazolyl)borate, poly[[μ‐hydrotris(3‐methyl‐2‐sulfanylidene‐2,3‐dihydro‐1H‐1,3‐imidazol‐1‐yl)borato]sodium(I)], [Na(C₁₂H₁₆BN₆S₃)] ([NaTm^Me]_n). NaTm^iPr and NaTm^Ph have similar dimeric molecular structures with κ³H,S,S′‐bonding, but they differ in that NaTm^Ph is crystallographically centrosymmetric (Z′ = 0.5) while NaTm^iPr contains one crystallographically centrosymmetric dimer and one dimer positioned on a general position (Z′ = 1.5). [NaTm^Me]_n is a one‐dimensional coordination polymer that extends along the a direction and which contains a hitherto unseen side‐on η²‐C=S‐to‐Na bond type. An overview of the structural preferences of alkali metal soft scorpionate complexes is presented. This analysis suggests that these thione‐based ligands will continue to be a rich source of interesting alkali metal motifs worthy of isolation and characterization.     

Magnesium,calcium and strontium salts of phenylacetic acid

Three alkaline earth metal salts of phenylacetic acid were examined and all were found to have similar structural types to analogous salts of benzoic and halobenzoic acids. Thus, a synchrotron study shows that the cations in catena‐poly[[[tetraaquamagnesium(II)]‐μ‐phenylacetato‐κ²O:O′] phenylacetate], {[Mg(C₈H₇O₂)(H₂O)₄](C₈H₇O₂)}_n, form a one‐dimensional coordination polymer that propagates through Mg—O—C—O—Mg interactions involving both crystallographically independent Mg centres (Z′ = 2) and through translation along the a axis. The polymeric chains pack to give alternate inorganic layers and organic bilayers. The Ca and Sr species catena‐poly[[[diaqua(phenylacetato‐κ²O,O′)calcium(II)]‐μ₃‐phenylacetato‐1′:1:1′′κ⁴O:O,O′:O′] monohydrate], {[Ca(C₈H₇O₂)₂(H₂O)₂]·H₂O}_n, and catena‐poly[[[diaqua(phenylacetato‐κ²O,O′)strontium(II)]‐μ₃‐phenylacetato‐1′:1:1′′κ⁴O:O,O′:O′] monohydrate], {[Sr(C₈H₇O₂)₂(H₂O)₂]·H₂O}_n, are essentially isostructural. Both form one‐dimensional coordination polymers through a carboxylate group that forms four M—O bonds. The polymeric chains propagate via 2₁ screw axes parallel to the b axis and are further linked in the bc plane by hydrogen bonding involving the non‐metal‐bound water molecule. Similarly to the Mg salt, both have inorganic layers that alternate with organic bilayers.     

A dihydroxidotetracopper(II) framework supported by 4,4′‐(adamantane‐1,3‐diyl)bis(1,2,4‐triazole) and benzene‐1,3,5‐tricarboxylate bridges

The new bifunctional ligand 4,4′‐(adamantane‐1,3‐diyl)bis(1,2,4‐triazole) (tr₂ad) and benzene‐1,3,5‐tricarboxylate sustain complementary coordination bridging for the three‐dimensional framework of poly[[bis[μ₃‐4,4′‐(adamantane‐1,3‐diyl)bis(1,2,4‐triazole)‐κ³N¹:N²:N^1′]bis(μ₄‐benzene‐1,3,5‐tricarboxylato‐κ⁴O¹:O^1′:O³:O⁵)di‐μ₃‐hydroxido‐κ⁶O:O:O‐tetracopper(II)] dihydrate], {[Cu₄(C₉H₃O₆)₂(OH)₂(C₁₄H₁₈N₆)₂]·2H₂O}_n. The net node is a centrosymmetric (μ₃‐OH)₂Cu₄ cluster [Cu—O = 1.9525 (14)–2.0770 (15) Å and Cu...Cu = 3.0536 (5) Å] involving two independent copper ions in tetragonal pyramidal CuO₄N and trigonal bipyramidal CuO₃N₂ environments. One carboxylate group of the anion is bridging and the other two are monodentate, leading to the connection of three hydroxide clusters and the generation of neutral coordination layers separated by 9.3583 (5) Å. The interlayer linkage is effected by μ₃‐tr₂ad ligands, with one triazole group N¹:N²‐bridging and the second monodentate [Cu—N = 1.9893 (19), 2.010 (2) and 2.411 (2) Å]. In total, the hydroxide clusters are linked to six close neighbors within the carboxylate layer and to four neighbors via tr₂ad bridges. Hydrogen bonding of solvent water molecules to noncoordinated triazole N atoms and carboxylate groups provides two additional links for the net, which adopts a 12‐connected topology corresponding to hexagonal closest packing. The study also introduces a new type of bis(triazole) ligand, which may find wider applications for supramolecular synthesis.     

A linear heterometallic bismuth–copper coordination polymer containing two types of organic ligands

In the linear coordination polymer catena‐poly[[[aqua(1,10‐phenanthroline‐κ²N,N′)copper(II)]‐μ‐pyridine‐2,6‐dicarboxylato‐κ⁴O²:O^2′,N,O⁶‐[(nitrato‐κ²O,O′)bismuth(III)]‐μ‐pyridine‐2,6‐dicarboxylato‐κ⁴O²,N,O⁶:O^6′] dihydrate], {[Bi^IIICu^II(C₇H₃NO₄)₂(NO₃)(C₁₂H₈N₂)(H₂O)]·2H₂O}_n, the Bi^III cation is O,N,O′‐chelated by the two pyridine‐2,6‐dicarboxylate ligands and O,O′‐chelated by the nitrate anion, the nine coordinating atoms conferring a tricapped trigonal prismatic environment on the metal centre. Each pyridine‐2,6‐dicarboxylate ligand uses one of its carboxylate O atoms to bind to an aqua(1,10‐phenanthroline)copper(II) unit, the Cu—O dative bonds giving rise to the formation of a ribbon motif. The Cu^II cation exhibits a square‐pyramidal geometry. The ribbon motif propagates along the shortest axis of the triclinic unit cell and the solvent water molecules are hydrogen bonded to the same ribbon.     

Triaqua­benzoatocalcium(II) monobenzoate: coordination polymer chains linked into a two‐dimensional framework by hydrogen bonds

In the title complex, catena‐poly[[[diaqua­calcium(I)]‐μ₂‐aqua‐μ₃‐benzoato‐κ⁴O:O,O′:O′] benzoate], {[Ca(C₇H₅O₂)(H₂O)₃](C₇H₅O₂)}_n, obtained by the reaction of CaCl₂ and potassium benzoate in water, the Ca atom is eight‐coordinated by four carboxyl­ate O atoms and four water mol­ecules. The structure consists of polymeric {[Ca(C₆H₅COO)(H₂O)₃]⁺}_∞ chains alternating with layers of uncoordinated C₆H₅COO⁻ anions. The nearly planar anions are linked to the chain by short hydrogen bonds to form a two‐dimensional network.     

Three isotypic polymeric complexes with rare earth cations,but‐2‐enoate anions and 4,4′‐(ethane‐1,2‐diyl)dipyridine and 4,4′‐(ethene‐1,2‐diyl)dipyridine bridging ligands

Three isotypic rare earth complexes, catena‐poly[[aquabis(but‐2‐enoato‐κ²O,O′)yttrium(III)]‐bis(μ‐but‐2‐enoato)‐κ³O,O′:O;κ³O:O,O′‐[aquabis(but‐2‐enoato‐κ²O,O′)yttrium(III)]‐μ‐4,4′‐(ethane‐1,2‐diyl)dipyridine‐κ²N:N′], [Y₂(C₄H₅O₂)₆(C₁₂H₁₂N₂)(H₂O)₂], the gadolinium(III) analogue, [Gd₂(C₄H₅O₂)₆(C₁₂H₁₂N₂)(H₂O)₂], and the gadolinium(III) analogue with a 4,4′‐(ethene‐1,2‐diyl)dipyridine bridging ligand, [Gd₂(C₄H₅O₂)₆(C₁₂H₁₀N₂)(H₂O)₂], are one‐dimensional coordination polymers made up of centrosymmetric dinuclear [M(but‐2‐enoato)₃(H₂O)]₂ units (M = rare earth), further bridged by centrosymmetric 4,4′‐(ethane‐1,2‐diyl)dipyridine or 4,4′‐(ethene‐1,2‐diyl)dipyridine spacers into sets of chains parallel to the [20] direction. There are intra‐chain and inter‐chain hydrogen bonds in the structures, the former providing cohesion of the linear arrays and the latter promoting the formation of broad planes parallel to (010).     

Chromium complexes bearing disubstituted organophosphate ligands and their use in ethylene polymerization

The crystal structures of three unusual chromium organophosphate complexes have been determined, namely, bis(μ‐butyl 2,6‐di‐tert‐butyl‐4‐methylphenyl hydrogen phosphato‐κO:κO′)di‐μ‐hydroxido‐bis[(butyl 2,6‐di‐tert‐butyl‐4‐methylphenyl hydrogen phosphato‐κO)(butyl 2,6‐di‐tert‐butyl‐4‐methylphenyl phosphato‐κO)chromium](Cr—Cr) heptane disolvate or {Cr₂(μ₂‐OH)₂[μ₂‐PO₂(OBu)(O‐2,6‐^tBu₂‐4‐MeC₆H₂)‐κO:κO′]₂[PO₂(OBu)(O‐2,6‐^tBu₂‐4‐MeC₆H₂)‐κO]₂[HOPO(OBu)(O‐2,6‐^tBu₂‐4‐MeC₆H₂)‐κO]₂}·2C₇H₁₆, [Cr₂(C₁₉H₃₂O₄P)₄(C₁₉H₃₃O₄P)₂(OH)₂]·2C₇H₁₆, denoted ( 1 )·2(heptane), [μ‐bis(2,6‐diisopropylphenyl) phosphato‐1κO:2κO′]bis[bis(2,6‐diisopropylphenyl) phosphato]‐1κO,2κO‐chlorido‐2κCl‐triethanol‐1κ²O,2κO‐di‐μ‐ethanolato‐1κ²O:2κ²O‐dichromium(Cr—Cr) ethanol monosolvate or {Cr₂(μ₂‐OEt)₂[μ₂‐PO₂(O‐2,6‐ⁱPr₂‐C₆H₃)₂‐κO:κO′][PO₂(O‐2,6‐ⁱPr₂‐C₆H₃)₂‐κO]₂Cl(EtOH)₃}·EtOH, [Cr₂(C₂H₅O)₂(C₂₄H₃₄O₄P)₃Cl(C₂H₆O)₃]·C₂H₆O, denoted ( 2 )·EtOH, and di‐μ‐ethanolato‐1κ²O:2κ²O‐bis{[bis(2,6‐diisopropylphenyl) hydrogen phosphato‐κO][bis(2,6‐diisopropylphenyl) phosphato‐κO]chlorido(ethanol‐κO)chromium}(Cr—Cr) benzene disolvate or {Cr₂(μ₂‐OEt)₂[PO₂(O‐2,6‐ⁱPr₂‐C₆H₃)₂‐κO]₂[HOPO(O‐2,6‐ⁱPr₂‐C₆H₃)₂‐κO]₂Cl₂(EtOH)₂}·2C₆H₆, [Cr₂(C₂H₅O)₂(C₂₄H₃₄O₄P)₂(C₂₄H₃₅O₄P)₂Cl₂(C₂H₆O)₂]·2C₆H₆, denoted ( 3 )·2C₆H₆. Complexes ( 1 )–( 3 ) have been synthesized by an exchange reaction between the in‐situ‐generated corresponding lithium or potassium disubstituted phosphates with CrCl₃(H₂O)₆ in ethanol. The subsequent crystallization of ( 1 ) from heptane, ( 2 ) from ethanol and ( 3 ) from an ethanol/benzene mixture allowed us to obtain crystals of ( 1 )·2(heptane), ( 2 )·EtOH and ( 3 )·2C₆H₆, whose structures have the monoclinic P2₁, orthorhombic P2₁2₁2₁ and triclinic P space groups, respectively. All three complexes have binuclear cores with a single Cr—Cr bond, i.e. Cr₂O₆P₂ in ( 1 ), Cr₂PO₄ in ( 2 ) and Cr₂O₂ in ( 3 ), where the Cr atoms are in distorted octahedral environments, formally having 16 ē per Cr atom. The complexes have bridging ligands μ₂‐OH in ( 1 ) or μ₂‐OEt in ( 2 ) and ( 3 ). The organophosphate ligands demonstrate terminal κO coordination modes in ( 1 )–( 3 ) and bridging μ₂‐κO:κO′ coordination modes in ( 1 ) and ( 2 ). All the complexes exhibit hydrogen bonding: two intramolecular O_phos…H—O_phos interactions in ( 1 ) and ( 3 ) form two {H[PO₂(OR)₂]₂} associates; two intramolecular Cl…H—O_Et hydrogen bonds additionally stabilize the Cr₂O₂ core in ( 3 ); two intramolecular O_phos…H—O_Et interactions and two O…H—O intermolecular hydrogen bonds with a noncoordinating ethanol molecule are observed in ( 2 )·EtOH. The presence of both basic ligands (OH^? or OEt^?) and acidic [H(phosphate)₂]^? associates at the same metal centres in ( 1 ) and ( 3 ) is rather unusual. Complexes may serve as precatalysts for ethylene polymerization under mild conditions, providing polyethylene with a small amount of short‐chain branching. The formation of a small amount of α‐olefins has been detected in this reaction.     

Two two‐dimensional MnII and NaI coordination polymers constructed by the flexible benzene‐1,4‐dioxy­acetate ligand

Two new two‐dimensional coordination polymers, poly­[[[aqua(2,2′‐bi­pyridine‐κ²N,N′)manganese(II)]‐μ₃‐p‐phenyl­enebis­(oxy­acet­ato)‐κ³O:O′:O′′] dihydrate], {[Mn(C₁₀H₈O₆)(C₁₀H₈N₂)(H₂O)]·2H₂O}_n, (I), and poly­[[di‐μ‐aqua‐bis­[aqua­sodium(I)]]‐μ₄‐p‐phenyl­enebis­(oxy­acetato)‐κO:O′,O′′:O′′′,O′′′′:O′′′′′], [Na₂(C₁₀H₈O₆)(H₂O)₄]_n, (II), have been synthesized and characterized by X‐ray single‐crystal diffraction. In (I), there are two 1,4‐BDOA²⁻ [p‐phenyl­enebis­(oxy­acetate) or, more commonly, benzene‐1,4‐dioxy­acetate] ligands, each lying about inversion centres, while in (II), there is one such ligand and it also has crystallographically imposed inversion symmetry. In (I), each Mn^II atom displays an octahedral MnN₂O₄ configuration, defined by three carboxyl O atoms of different 1,4‐BDOA²⁻ groups, two N atoms of one 2,2′‐bi­pyridine ligand and one water mol­ecule. In (II), each Na^I atom is octahedrally coordinated by one ether O atom, two carboxyl O atoms of different 1,4‐BDOA²⁻ ligands and three water mol­ecules. The metal ions in complexes (I) and (II) are bridged by 1,4‐BDOA²⁻ groups into two‐dimensional layer structures. Furthermore, three‐dimensional supramolecular networks are constructed via hydrogen bonds in (I) and (II), and by additional π–π stacking interactions in (I).