Kinetico‐Mechanistic Insights on the Assembling Dynamics of Allyl‐Cornered Metallacycles: The PtNpy Bond is the Keystone

The square‐like homo‐ and heterometallamacrocycles [{Pd(η³‐2‐Me‐C₃H₄)( L ⁿ )₂}₂{M(dppp)}₂](CF₃SO₃)₆ (dppp=1,3‐bis(diphenylphosphino)propane) and [{Pd(η³‐2‐Me‐C₃H₄)( L¹ )₂}₂{M(PPh₃)₂}₂](CF₃SO₃)₆ [py=pyridine, M=Pd, Pt, L ^{n =}4‐PPh₂py ( L¹ ), 4‐C₆F₄PPh₂py ( L² )] containing allyl corners were synthesised by antisymbiotic self‐assembly of the different palladium and platinum metallic corners and the ambidentate N,P ligands. All the synthesised assemblies displayed a complex dynamic behaviour in solution, the rate of which is found to be dependent on the electronic and/or steric nature of the different building blocks. A kinetico‐mechanistic study by NMR line shape analysis of the dynamics of some of these assemblies was undertaken in order to determine the corresponding thermal activation parameters. Both an enhanced thermodynamic stability and slower dynamics were observed for platinum‐pyridine‐containing species when compared with their palladium analogues. Time‐dependent NMR spectroscopy in combination with ESI mass spectrometry was used to study the exchange between the assemblies and their building blocks, as well as that occurring between different metallamacrocycles. Preliminary studies were carried out on the activity of some of the metallamacrocyclic compounds as catalytic precursors in the allylic substitution reaction, and the results compared with that of the monometallic allylic corner [Pd(η³‐2‐Me‐C₃H₄)( L¹ )₂]⁺.     

3,6-二(N-咪唑/苯并咪唑基)哒嗪配体配合物的合成、结构、荧光及光催化性能

用溶剂热法设计、合成了4个金属-有机配合物[Mn(L¹)₄(OH)₂](1),{[MnL¹(H₂O)₄]SO₄}_n(2),[CdL²(NO₃)₂]_n(3)和{[Co(L²)₂](PF₆)₂}_n(4),(L¹=3,6-二(N-咪唑基)哒嗪,L²=3,6-二(N-苯并咪唑基)哒嗪),并通过元素分析、红外、X射线单晶衍射对配合物结构进行了表征,测试结果表明配合物1具有单核结构,2为一维链结构,配合物3和4均为二维网状结构。此外,对配合物3和4的固态荧光性能及光催化的性能做了进一步研究。     

A Design Strategy for Single‐Stranded Helicates using Pyridine‐Hydrazone Ligands and PbII

The reactions of py‐hz ligands ( L1–L5 ) with Pb(CF₃SO₃)₂?H₂O resulted in some rare examples of discrete single‐stranded helical Pb^II complexes. L1 and L2 formed non‐helical mononuclear complexes [Pb L1 (CF₃SO₃)₂]?CHCl₃ and Pb L2 (CF₃SO₃)₂][Pb L2 CF₃SO₃]CF₃SO₃?CH₃CN, which reflected the high coordination number and effective saturation of Pb^II by the ligands. The reaction of L3 with Pb^II resulted in a dinuclear meso‐helicate [Pb₂ L3 (CF₃SO₃)₂Br]CF₃SO₃?CH₃CN with a stereochemically‐active lone pair on Pb^II. L4 directed single‐stranded helicates with Pb^II, including [Pb₂ L4 (CF₃SO₃)₃]CF₃SO₃?CH₃CN and [Pb₂ L4 CF₃SO₃(CH₃OH)₂](CF₃SO₃)₃?2 CH₃OH?2 H₂O. The acryloyl‐modified py‐hz ligand L5 formed helical and non‐helical complexes with Pb^II, including a trinuclear Pb^II complex [Pb₃ L5 (CF₃SO₃)₅]CF₃SO₃?3CH₃CN?Et₂O. The high denticity of the long‐stranded py‐hz ligands L4 and L5 was essential to the formation of single‐stranded helicates with Pb^II.     

Solid state thermal isomerisation of diethylenetriamine complexes of NiX2 (X=NO3, ClO4, BF4 and CF3SO3)

Summary [Ni(dien)₂]X₂·nH₂O (dien=diethylenetriamine; n=0, X=NO₃ or CF₃SO₃; n=0.5, X=ClO₄ or BF₄ and n=2, X=CF₃SO₃) complexes have been prepared and investigated thermally in the solid state. [Ni(dien)₂](NO₃)₂ (1) and [Ni(dien)₂](CF₃SO₃)₂ (2) undergo endothermic irreversible phase transitions (209–247°C and 184–205°C; H=5.6 kJ mol^–1 and 7.7 kJ mol^–1 for (1) and (2), respectively). [Ni(dien)₂](ClO₄)₂·0.5H₂O (3) shows an endothermic irreversible phase transition after deaquation (201–216°C; H=7.7 kJ mol^–1). [Ni(dien)₂](BF₄)₂·0.5H₂O also shows an endothermic irreversible phase transition after deaquation, accompanied by partial decomposition. All the complexes possess octahedral geometry with the ligands arranged meridionally. The phase transitions are explained in terms of conformational changes of the triamine chelate rings.Author to whom all correspondence should be directed. Supplementary data available: i.r. spectra (Table 4) and x-ray diffraction patterns (Table 5).     

Silver(I) complexes of triazine derivatives having stepped π–π interactions and 2D sheets

Reactions of silver(I) perchlorate and triflate with the triazine ligands 2,4,6-trimethoxy-1,3,5-triazine (L¹) and 2,4,6-triphenyl-1,3,5-triazine (L²) have provided three novel silver complexes: [Ag(L¹)₂](ClO₄) (1), [Ag(L¹)₂](CF₃SO₃) (2) and [Ag₂(L²)(CF₃SO₃)₂] (3). The crystal structures of these complexes have been determined by single-crystal X-ray diffraction. Each complex exhibits distinct coordination behavior and different frameworks. Complex 1 has a 1D stepped framework in which one crystallographically independent metal center interacts with two L¹ molecules and strong π–π interactions between the triazine planes of two L¹ molecules exist. On the other hand, complex 2 has a herringbone-like molecular packing in which the triflate ions are arranged between mononuclear complex cations. In complex 3, L² molecules are suspended between two double chains of silver triflate through the coordination to silver(I) ions to form the 2D sheet network structure. The factors that influence the crystal structure and packing are discussed.     

Linkage isomeric oxamate chelates: rac‐bis(ethane‐1,2‐diamine)oxamatocobalt(III) bis(trifluoromethanesulfonate) dihydrate and Λ(+)578‐bis(ethane‐1,2‐diamine)[oxamato(2−)]cobalt(III) trifluoromethanesulfonate

The structures of rac‐bis(ethane‐1,2‐diamine)(oxamato‐κ²O¹,O²)cobalt(III) bis(trifluoromethanesulfonate) dihydrate, [Co(C₂H₂NO₃)(C₂H₈N₂)₂](CF₃SO₃)₂·2H₂O, (I), and Λ(+)₅₇₈‐bis(ethane‐1,2‐diamine)[oxamato(2−)‐κ²N,O¹]cobalt(III) trifluoromethanesulfonate, [Co(C₂HNO₃)(C₂H₈N₂)₂]CF₃SO₃, (II), are compared. Together, the two complexes constitute the first pair of linkage isomers of bidentate oxamate available for structural comparison.     

Silver(I) complexes with halo-substituted cyanoanilines: synthesis,characterization and antibacterial activity

Four Ag(I) complexes, [Ag(L₁)₂](NO₃) (1), [Ag(L₂)(NO₃)] (2), [Ag(L₃)₃](NO₃) (3), and [Ag(L₄)₂](NO₃) (4), with ligands derived from halo-containing cyanoanilines (L₁ = 4-amino-3fluorobenzonitrile, L₂ = 4-amino-3-chlorobenzonitrile, L₃ = 4-amino-3-bromobenzonitrile, L₄ = 4-amino-2-bromobenzonitrile) were synthesized and characterized by C, H, and N elemental analysis, IR and ¹H NMR spectroscopy and single crystal X-ray diffraction. Complexes 1–4 crystallized in the triclinic space group C2/c, P2(1)/n, P-1 and C2/c, respectively. In 1 and 4, Ag⁺ is four-coordinate with L₁ or L₄ to form 1-D _∞{[Ag(L₁/L₄)₂]⁺} polymeric cations. In 2, Ag⁺ is three-coordinate by two L₂ ligands and one NO₃^? ligand to form a 1-D _∞{[Ag(L₂)(NO₃)]} zigzag chain. In 3, Ag⁺ is four-coordinate by L₃ to form a dinuclear [Ag(L₃)₃]⁺ cation. The NO₃^? is a 4-connector bridging group in 1 and 3 and a 5-connector bridging group in 2 and 4. The intermolecular hydrogen bonds and Ag?O weak interactions play important roles in forming 3-D networks of 1–4. The antibacterial activities for 1–4 were evaluated against Bacillus subtilis, Staphylococcus aureus and Escherichia coli with MTT method. The antibacterial results indicated that 2 showed the best inhibitory activity against the test bacterial strains, and was as potent as chloramphenicol.     

Synthesis and crystal structures of new palladium catalysts for the hydromethoxycarbonylation of alkenes

The preparation and structural characterization of dimeric Pd(I)-Pd(I) complex [Pd₂{(PPh₃)(OSO₂CF₃)}₂].CH₂Cl₂ (1) and three palladium center [Pd₃{(PPh₃)(OSO₂CF₃)}₂] (2) and [Pd₃(PPh₃)₄](SO3CF₃)₂ (3) complexes are reported. The complexes exhibit coordination in which the phosphine phenyl ring is used to stabilize Pd(I) centers in (1) and, Pd(I) and Pd(0) centers in (2) and (3) by acting as π electron donors. The complexes were characterized by single crystal X-ray crystallography.     

Unusually facile syntheses of [RuII(bpy)3]2+ (bpy = 2,2′-bipyridine) and [RuII(phen)3]2+ (phen = 1,10-phenanthroline)

The salts [Ru^II(L–L)₃](CF₃SO₃)₂ (L–L = bpy or phen) have been prepared in high yields via reactions of [Ru^II(DMF)₆](CF₃SO₃)₂ (DMF = N,N-dimethylformamide), generated in situ by reduction of [Ru^III(DMF)₆]-(CF₃SO₃)₃, with an excess of bpy or phen at room temperature in DMF solutions.     

Synthesis,characterization, crystal structures,and superoxide dismutase activity of copper(II) octahedral complexes containing tri- and monodentate ligands

Three new copper(II) complexes [Cu(PSBP)₂](NO₃)(BF₄) (1), [Cu(DAPBMA)₂](BF₄)₂ (2), and [Cu(ImH)₄(NO₃)₂] (3), where PSBP = 4-phenylsemicarbazide-2-benzoylpyridine, DAPBMA = 2,6-diacetylpyridine-bis-4-methoxyaniline, and ImH = Imidazole, have been synthesized and characterized by elemental analysis, FAB mass spectrometry, magnetic susceptibility, X-band electron paramagnetic resonance (EPR), electronic spectroscopy, and cyclic voltammetry. Frozen solution EPR spectra of the complexes have axial features with g _∥ > g _⊥ > 2.003 suggesting the presence of a d _{x ²? y ²} ground state. Single crystal X-ray analyses of 1–3 reveal the presence of distorted octahedral geometry. All complexes exhibit significant superoxide dismutase activity.     

Coumarin-naphthohydrazone ligand with a rare coordination mode to form Mn(II) and Co(II) 1-D coordination polymers: synthesis,characterization, and crystal structure

The hydrazone (E)-3-hydroxy-N’-(1-(2-oxo-2H-chromen-3-yl)ethylidene)-2-naphthohydrazide (H₂L) was synthesized from the reaction of 3-acetylcoumarin and 3-hydroxy-2-naphthoic hydrazide in methanol. Compounds [Mn(H₂L)(NO₃)₂(CH₃OH)]·CH₃OH (1a), [Mn(HL)(NO₃)(CH₃OH)]_n (1b), [Co(HL)(NO₃)(CH₃OH)]_n (2), and [Cu(HL)(NO₃)] (3) were obtained by reaction of an equimolar amount of H₂L with nitrate salts of Mn(II), Co(II), or Cu(II) in methanol. The reaction of ligand and Mn(NO₃)₂·4H₂O was also carried out in the presence of sodium azide which led to the 1-D coordination polymer, [Mn(HL)(N₃)(CH₃OH)]_n (4). All of the synthesized compounds were characterized by elemental analyses and spectroscopic methods. Single-crystal X-ray analysis of 1–4 indicated that H₂L is neutral (in 1a) or mononegative ligand (in 1b, 2, 3 and 4). In 1b, 2 and 4 the 1-D polymeric chain is found by a rare coordination mode of this kind of hydrazone ligand since the naphtholic oxygen is coordinated to the neighboring metal ions while the NH moiety of hydrazone remains intact, also confirmed by FT-IR spectroscopic studies. The thermal stability of 2 and 4 were also studied from 30–1000 °C.     

Platinum complexes bearing 2,2′-dipyridylamine ligand

The replacement of the iodide ligands in the complex [PtI₂(dpa)] (1) (dpa is 2,2′-dipyridylamine) by silver triflate in acetonitrile afforded the compound [Pt(dpa)(MeCN)₂](SO₃CF₃)₂ (2). Homoleptic complexes [Pt(dpa)₂](X)₂ (3·(X)₂) were synthesized by the treatment of [PtI₂(dpa)] (1) with 2,2′-dipyridylamine in the presence of silver salts AgX in methanol (X = NO₃) or acetonitrile (X = SO₃CF₃). The deprotonation of the complex [3](SO₃CF₃)₂ to give the homoleptic complex [Pt(dpa-H)₂] (4) was performed by two methods, e.g., by the treatment of [3](SO₃CF₃)₂ with 2 equiv. of NaOH in methanol or by the addition of excess Et₃N to a suspension of [3](SO₃CF₃)₂ in methanol. The structures of compounds 1–4 were established by elemental analyses, high resolution electrospray ionization mass spectrometry, IR and NMR spectroscopy; the crystal structure of complexes [2](SO₃CF₃)₂, [3](NO₃)₂·H₂O, [3](SO₃CF₃)₂·2H₂O, and 4 were determined by single-crystal X-ray diffraction.     

Kinetic studies of dicopper complexes in catechol oxidase model reaction by using an approximationless evaluating method

The oxidation of 3,5-di-tert-butylcatechol to 3,5-di-tert-butyl-o-benzoquinone catalyzed by dinuclear copper(II) complexes {[Cu₂(L¹)(CF₃SO₃)₂(H₂O)₄]-(CF₃SO₃)₂ (1) and [Cu₂(L²O)](CF₃SO₃)₂ (2)| has been investigated in methanol saturated with O₂ at ambient temperature. Detailed kinetic studies were carried out and for the treatment the fitting software ZiTa was applied. On the basis of the results in the kinetic studies a possible mechanism of the catalytic reaction is proposed.This revised version was published online in December 2005 with corrections to the Cover Date.     

New polynuclear compounds based on N-benzyliminodipropionic acid: solution studies,synthesis, and X-ray crystal structures

Three new polynuclear compounds based on a dicarboxylic acid ligand are reported. In particular, two Cu(II) coordination compounds, [Cu₂(H₂O)₆(Hbzlidp)₂](CF₃SO₃)₂·2H₂O (1) and [Cu(NO₃)(Hbzlidp)]_∞ (2) (bzlidp^2? = N-benzyliminodipropionate anion), and a Ni(II) dinuclear compound, [Ni₂(H₂O)₄(bzlidp)₂] (3), were synthesized and characterized by IR spectroscopy, elemental analysis and single crystal X-ray diffraction. Different structures were obtained depending on the reaction conditions. The structural analyses reveal that 1 was formed by dinuclear [Cu₂(H₂O)₆(Hbzlidp)₂]²⁺ units built by two copper(II) ions joined through two Hbzlidp^? ligands, while 2 was formed by pairs of Cu(II) centers bridged by four syn,syn carboxylate groups to generate “paddle wheel” units. The dinuclear copper units are arranged in a rhombus type grid, in a 2-D layer structure. In both cases, the N was protonated and not coordinated to the metal center. Compound 3 was formed by [Ni₂(H₂O)₄(bzlidp)₂] neutral dinuclear units, with octahedral Ni(II) centers. Solution studies of the ligand–M(II) systems (M(II) = Mn, Co, Ni, Cu, Zn, Cd, and Pb) were also carried out.     

Toxic metal complexes of macrocyclic cyclen molecule – synthesis,structure and complexing properties

Toxic metal (Cd²⁺, Hg²⁺, Pb²⁺, and Ag⁺) complexes with the tetradentate macrocyclic ligand - cyclen (1,4,7,10-tetraazacyclododecane, [12]aneN₄, L) were prepared and studied in the solid state by IR, X-ray diffraction, elemental and thermal analysis. Diffraction results have yielded three molecular structures, [Cd([12]ane-κ⁴N^1,4,7,10)(NO₃)₂)] (1), [Hg([12]ane-κ⁴N^1,4,7,10)(NO₃-κ²O,O`)]NO₃ (2), [Pb₂([12]ane-κ⁴N^1,4,7,10)₂][Pb(NO₃)₆] (3) and one polymeric structure {[Ag₂([12]ane-κ³N^1,4,7)(μ₂-[12]aneN¹⁰)](NO₃)₂?2H₂O)}_n (4) featuring a unique coordination mode not observed before with cyclen as a ligand. The monodentate (1) and chelate (with small bite angle 50.3(3)°, (2) coordination modes of nitrate ligands were confirmed. Stereochemically active 6s² lone pair was suggested in 3 and DFT results confirmed no significant metal–metal covalent bond. The stability constants of the complexes with Cd²⁺ and Pb²⁺ ions were determined by potentiometric methods in aqueous solutions. Additionally, the structures of complexes in solution were observed by ¹H NMR. Both methods confirm similar cyclen complexing properties toward Zn²⁺ biometal and Cd²⁺, Pb²⁺ toxic metals.     

Synthesis,crystal structures and thermal stabilities of zinc coordination polymers containing the 3-hydrazino-4-amino-1,2,4-triazole ligand

Two zinc coordination polymers, {[Zn(HATr)₂](NO₃)₂}_n (1) and {[Zn₂(HATr)₄](ZnCl₄)(NO₃)₂·H₂O}_n (2), were synthesized from reactions of 3-hydrazino-4-amino-1,2,4-triazole dihydrochloride (HATr·2HCl) with Zn(NO₃)₂. The polymers were characterized by single-crystal X-ray diffraction, Fourier transform infrared spectroscopy (FTIR), elemental analysis, and differential scanning calorimetry. The crystal structures revealed that 1 and 2 have 1-D-chain structures, which were further assembled to form 3-D-frameworks by hydrogen bonds. Thermal analyses showed that these two compounds have thermal stability up to 280 °C. The energies of combustion, enthalpies of formation, critical temperatures of thermal explosion, entropies of activation (ΔS^≠), enthalpies of activation (ΔH^≠), and free energies of activation (ΔG^≠) were also measured and calculated. Furthermore, the sensitivities of 1 and 2 toward impact, friction, and static were determined, which revealed that 1 and 2 were less sensitive than Ni(N₂H₄)₃(NO₃)₂.     

Two- and Three-dimensional Frameworks with (6,3) and (10,3)-a Topology from Self-assembly of Three-connecting Organic Ligands with Cadmium(II) and Silver(I) Salts

Assembly of three-connecting ligands 1,3,5-tris(1-imidazolyl)benzene (tib) and 1,3,5-tris(imidazol-1-ylmethyl)-2,4,6-trimethylbenzene (titmb) with cadmium(II) and silver(I) salts provide new metal-organic frameworks, [Cd(tib)₂](NO₃)₂·4H₂O (1), [Ag(tib)(PPh₃)](CF₃SO₃) (2) and [Ag(titmb)(PPh₃)](CF₃SO₃)·1.5H₂O (3) (PPh₃=triphenylphosphine). Single-crystal X-ray diffraction studies reveal that complexes 1 and 3 are two-dimensional honeycomb networks, while complex 2 is a noninterpenetrated three-dimensional architecture with (10,3)-a topology. The results indicate that the nature (structure and flexibility) of the organic ligands and the bulky auxiliary ligand have great impact on the assembly and structure of metal-organic frameworks. The photoluminescent properties of the synthesized complexes were studied in the solid state at room temperature.     

3,6-二(N-咪唑/苯并咪唑基)哒嗪配体配合物的合成、结构、荧光及光催化性能

用溶剂热法设计、合成了4个金属-有机配合物[Mn(L¹)₄(OH)₂] (1),{[MnL¹(H₂O)₄]SO₄}_n (2),[CdL²(NO₃)₂]_n (3)和{[Co(L²)₂](PF₆)₂}_n (4),(L¹=3,6-二(N-咪唑基)哒嗪,L²=3,6-二(N-苯并咪唑基)哒嗪),并通过元素分析、红外、X射线单晶衍射对配合物结构进行了表征,测试结果表明配合物1具有单核结构,2为一维链结构,配合物3和4均为二维网状结构。此外,对配合物3和4的固态荧光性能及光催化的性能做了进一步研究。     

Structural control in palladium(II)-catalyzed enantioselective allylic alkylation by new chiral phosphine-phosphite and pyridine-phosphite ligands

The ligands 6-[(diphenylphosphanyl)methoxy]-4,8-di-tert-butyl-2,10-dimethoxy-5,7-dioxa-6-phosphadibenzo[a,c]cycloheptene, 1, (S)-4-[(diphenylphosphanyl)methoxy]-3,5-dioxa-4-phosphacyclohepta[2,1-a;3,4a′]dinaphthalene, (S)-2, and (S)-4-[(diphenylphosphanyl)methoxy]-2,6-bis-trimethylsilanyl-3,5-dioxa-4-phosphacyclohepta[2,1-a;3,4-a′]dinaphthalene, (S)-3, (S)-2-(3,5-dioxa-4-phosphacyclohepta[2,1-a;3,4-a′]dinaphthalen-4-yloxymethyl)pyridine, (S)-4, and (S)-2-(3,5-dioxa-4-phosphacyclohepta[2,1-a;3,4-a′]dinaphthalen-4-yloxy)pyridine, (S)-5, have been easily prepared.The cationic complexes [Pd(η³-C₃H₅)(L-L′)]CF₃SO₃ (L–L′=1–(S)-5) and [Pd(η³-PhCHCHCHPh)(L–L′)]CF₃SO₃ (L–L′=(S)-2–(S)-4) were synthesized by conventional methods starting from the complexes [Pd(η³-C₃H₅)Cl]₂ and [Pd(η³-PhCHCHCHPh)Cl]₂, respectively. The behavior in solution of all the π-allyl- and π-phenylallyl-(L–L′)palladium derivatives 6–14 was studied by ¹H, ³¹P{¹H}, ¹³C{¹H} NMR and 2D-NOESY spectroscopy. As concerns the ligands (S)-4 and (S)-5, a satisfactory analysis of the structures in solution was possible only for palladium–allyl complexes [Pd(η³-C₃H₅)((S)-4)]CF₃SO₃, 11, and [Pd(η³-C₃H₅)((S)-5)]CF₃SO₃, 12, since the corresponding species [Pd(η³-PhCHCHCHPh)((S)-4)]CF₃SO₃, 13, and [Pd(η³-PhCHCHCHPh)((S)-5)]CF₃SO₃, 14, revealed low stability in solution for a long time. The new ligands (S)-2–(S)-5 were tested in the palladium-catalyzed enantioselective substitution of (1,3-diphenyl-1,2-propenyl)acetate by dimethylmalonate. The precatalyst [Pd(η³-C₃H₅)((S)-2)]CF₃SO₃ afforded the allyl substituted product in good yield (95%) and acceptable enantioselectivities (71% e.e. in the S form). A similar result was achieved with the precatalyst [Pd(η³-C₃H₅)((S)-3)]CF₃SO₃. The nucleophilic attack of the malonate occurred preferentially at allylic carbon far from the binaphthalene moiety, namely trans to the phosphite group. When the complexes containing ligands (S)-4 and (S)-5 were used as precatalysts, the product was obtained as a racemic mixture in high yield. The number of the configurational isomers of the Pd-allyl intermediates present in solution in the allylic alkylation and the relative concentrations are considered a determining factor for the enantioselectivity of the process.     

Ferromagnetic Ordering in the Layer‐Structured Pd(HS2O7)2

The reaction of (NO₂)(CF₃SO₃) and elemental palladium in oleum (65 % SO₃) leads to violet single crystals of Pd(HS₂O₇)₂ (monoclinic, P2₁/c, Z=2, a=927.80(9), b=682.58(7), c=920.84(9) pm, β=117.756(2)°, wR₂=0.0439). In the crystal structure, the Pd²⁺ ions show an uncommon octahedral coordination of six oxygen atoms belonging to six HS₂O₇^? ions. The linkage of [PdO₆] octahedra and the hydrogendisulfate anions leads to a layer structure, and the layers are held together by hydrogen bonds. The unusual coordination of the Pd²⁺ ions results in an electronic d⁸ high‐spin configuration, which leads to the paramagnetic behavior of the compound. Moreover, at low temperature, a ferromagnetic ordering was observed with a Curie temperature of 8 K.