Polynuclear manganese complexes with the dicarboxylate ligand m-phenylenedipropionate: a hexanuclear mixed-valence (3Mn(III), 3Mn(IV)) complex

The dicarboxylate group m-phenylenedipropionate (mpdp(2)(-)) has been used for the synthesis of four new Mn compounds of different nuclearities and oxidation states: [Mn(2)O(mpdp)(bpy)(2)(H(2)O)(MeCN)](ClO(4))(2) (3), [Mn(3)O(mpdp)(3)(py)(3)](ClO(4)) (4), [Mn(3)O(mpdp)(3)(py)(3)] (5), and [Mn(6)O(7)(mpdp)(3)(bpy)(3)](ClO(4)) (6). Compound 3 (2Mn(III)) contains a [Mn(2)(micro-O)](4+) core, whereas 5 (Mn(II), 2Mn(III)) and 4 (3Mn(III)) contain the [Mn(3)(micro(3)-O)](6+,7+) core, respectively. In all three compounds, the mpdp(2)(-) ligand is flexible enough to adopt the sites occupied by two monocarboxylates in structurally related compounds, without noticeable distortion of the cores. Variable-temperature magnetic susceptibility studies establish that 3 and 5 have ground-state spin values of S = 0 and S = 1/2, respectively. Compound 6 is a highly unusual 3Mn(III), 3Mn(IV) trapped-valent compound, and it is also a new structural type, with six Mn atoms disposed in a distorted trigonal antiprismatic topology. Its electronic structure has been explored by variable-temperature measurements of its dc magnetic susceptibility, magnetization vs field response, and EPR spectrum. The magnetic data indicate that it possesses an S = 3/2 ground state with an axial zero-field splitting parameter of D = -0.79 cm(-)(1), and this conclusion is supported by the EPR data. The combined results demonstrate the ligating flexibility of the mpdp(2)(-) ligand and its usefulness in the synthesis of a variety of Mn(x) species.     

One ligand different metal complexes: Biological studies of titanium(IV), tin(IV) and gallium(III) derivatives with the 2,6-dimethoxypyridine-3-carboxylato ligand

The reaction of 2,6-dimethoxypyridine-3-carboxylic acid (DMPH) with different precursors [Ti(η⁵-C₅H₅)₂Cl₂], [Ti(η⁵-C₅H₄Me)₂Cl₂], [Ti(η⁵-C₅H₄SiMe₃)(η⁵-C₅H₅)Cl₂], [Ti(η⁵-C₅Me₅)Cl₃], SnMe₃Cl and Ga^tBu₃ yielded the complexes [Ti(η⁵-C₅H₅)₂(DMP-κO)₂] (1), [Ti(η⁵-C₅H₄Me)₂(DMP-κO)₂] (2), [Ti(η⁵-C₅H₄SiMe₃)(η⁵-C₅H₅)(DMP-κO)₂] (3), [Ti(η⁵-C₅Me₅)(DMP-κ²O,O′)₃] (4), [SnMe₃(μ-DMP-κO:κO′)]_∞ (5), and [Ga^tBu₂(μ-DMP-κO:κO′)]₂ (6). 1-6 have been characterized by spectroscopic methods and the molecular structure of the complexes 1, 2, 3, 5 and 6 have been determined by X-ray diffraction studies. The cytotoxic activity of 1-6 was tested against the tumour cell lines human adenocarcinoma HeLa, human myelogenous leukaemia K562, human malignant melanoma Fem-x and human breast carcinoma MDA-MB-361. The results of this study show a higher cytotoxicity of the tin(IV) and gallium(III) derivatives in comparison to their titanium(IV) counterparts. Furthermore, the different titanium compounds showed differences in their cytotoxicities with a higher activity of complex 4 (mono-(cyclopentadienyl) derivative) compared to that of 1-3 (bis-(cyclopentadienyl) complexes). A qualitative UV-vis study of the interactions of these complexes with DNA has also been carried out.     

Investigations of chromium(III), manganese(III), tin(II) and lead(II) dithiocarbamate complexes

Piperidine-, morpholine-4-, N-methylpiperazine-4- and thiornorpholine-4-carbodithioate complexes of chromium(III), manganese(III), tin(II) and lead(II) are prepared and characterized by chemical analyses, spectroscopic methods (I.R. and electronic spectra), magnetic susceptibilities, conductivity measurements and mass spectra. The complexes are of the type M(R₂dtc)n, where n is the oxidation number of the metal ion. Where possible a tentative stereochemistry of the complexes is discussed on the basis of the results obtained. In all the complexes the dithiocarbamate ligands show bidentate behaviour.     

Analytical separation of antimony(III) from bismuth(III), lead(II), gallium(III), thallium(III), tellurium(IV) and tin(IV) with cyanex 302

A method is proposed for the separation of antimony(III) (100–400 g) from bismuth(III), lead(II), gallium(III), thallium(III), tellurium(IV) and tin(IV) from an aqueous solution of pH 0.5–1.5 using 8×10^–3–1×10^–2 mol dm^–3 cyanex 302 dissolved in toluene as an extractant. The antimony is stripped from the cyanex phase with water and determined spectrophotometrically with iodide. Various experimental parameters are optimized and the probable 13 stoichiometry of the extracted species is evaluated. The method is applicable to the analysis of alloys and pharmaceutical samples. The separation and determination take only 20 min.     

Iron(III) complexes of a tetradentate tripodal ligand N,N′,N″-tris (2-benzimidazolyl-methyl)amine

Summary Fe^III complexes of a tetradentate ligand with pendant benzimidazolyl groups have been synthesized and characterized. Room temperature Mössbauer spectra depict a quadruple split doublet in the case of NO _inf3 ^p– as co-ligand, while a nearly symmetrical one line spectrum is obtained for complexes with Cl^–as co-ligand. The isomer shift values are towards the lower end of the range found for other high spin Fe^III complexes. ¹H-n.m.r. spectra of the complexes reveal relatively broad linewidths with large isotropic shifts. Paramagnetically shifted resonances are observed in the range of –10.0–+70.0 p.p.m.Author to whom all correspondence should be directed.     

Versatile ligand behavior of hydrotris(4-ethyl-3-methyl-5-thioxo-1,2,4-triazolyl)borate. Syntheses and crystal structures of Cu(I) and Bi(III) complexes

Preparations of copper(I) and bismuth(III) complexes of hydrotris(4-ethyl-3-methyl-5-thioxo-1,2,4-triazolyl)borate (Tr(Et,Me)) are described. These complexes have been characterized by means of spectroscopy and microanalysis. Molecular structures of [Cu(Tr(Et,Me))](2) x 2.5CH(3)CN x 0.5H(2)O (3a) and [Bi(Tr(Et,Me))(2)]NO(3) x 2CHCl(3) (4a) have been determined by single-crystal X-ray diffraction. In the centrosymmetric dimeric copper(I) complex, Tr(Et,Me) acts in the k(3)S,S',H:kS' ' coordination mode. The metal is found in a distorted trigonal geometry as the ligand exhibits an "S(3)-inverted" conformation at the boron center so that a weak [B-H.Cu] agostic interaction renders the overall coordination of the (3 + 1) type. On the other hand, in the bismuth complex, Tr(Et,Me) presents the k(3)S,S',S' ' coordination mode and the "S(3)-normal" conformation. The metal is found in a regular octahedral geometry bound by six thioxo groups of two ligands. Species distributions in solution have been studied using electrospray ionization mass spectrometry upon dissolution of 3a and 4a crystals in acetonitrile. Monomeric and polynuclear copper(I) complexes with different M:L ratios are present in solution, while for 4a only the monomeric species is present.     

Direct potentiometric determination of tin(II) and (IV), antimony(III), thallium(III), rhenium(VII), and bismuth(III) with cetylpyridinium chloride

Summary The precipitation titrations of the following elements vs. cetylpyridinium chloride were investigated: Rhenium as perrhenate, tin as the (II) and (IV) species, antimony(III), thallium(III), and bismuth(III) as their halogen complexes. Optimum conditions for the determinations are described. Of the elements examined only thallium(III) also could be titrated potentiometrically vs. tetraphenylarsonium chloride. Titrations were monitored with a simple sensor consisting of a graphite rod coated with poly(vinyl chloride) and dioctylphthalate, and a double-junction reference electrode.

---

Direkte potentiometrische Bestimmung von Zinn(II) und (IV), Antimon(III), Thallium(III), Rhenium(VII) und Bismut(III) mit Hilfe von Cetylpyridiniumchlorid

Zusammenfassung Die Fällungstitration der genannten Elemente mit Cetylpyridiniumchlorid wurde untersucht: Re als Perrhenat; Zinn in 3- und 4wertiger Form; Sb(III), Tl(III) und Bi(III) in Form ihrer Halogenkomplexe. Die optimalen Bedingungen werden mitgeteilt. Nur Thallium(III) kann auch potentiometrisch gegen Tetraphenylarsoniumchlorid titriert werden. Die Titrationen werden mit Hilfe eines einfachen Sensors kontrolliert, der aus einem mit Polyvinylchlorid und Dioctylphthalat überzogenen Graphitstab besteht sowie einer double-junction Bezugselektrode.

     

Iron(III) complexes with a tripodal N3O ligand containing an internal base as a model for catechol intradiol-cleaving dioxygenases

A bis(mu-alkoxo)-bridged dinuclear iron(III) complex [Fe(L)(NO3)]2(NO3)2 [1; HL = N,N-bis(2-pyridylmethyl)-N-(2-hydroxyethyl)amine] of the tripodal N3O ligand was prepared as a biomimetic model for the intradiol-cleaving dioxygenase enzymes. The reaction of 1 and catechol in the presence of excess triethylamine gave the catecholate (CAT) chelate bis(mu-alkoxo)-bridged dinuclear iron(III) complex [Fe(L)(CAT)]2 (2). The molecular structures of complexes 1 and 2 were determined by X-ray crystallography. Diiron complexes 1 and 2 contain the same bis(mu-alkoxo)diiron diamond core. All heteroatoms (N3O) of the ligand are coordinated to the iron center in complex 1 with two pyridine nitrogen atoms on the axial bonds, while one of the pyridyl arms of the ligand is left uncoordinated in complex 2. The interaction of the diiron complex 1 and 3,5-di-tert-butylcatechol (H2DBC) was investigated by electronic and mass spectroscopy. Complex 1 displays the intradiol-cleaving dioxygenase activity, and the coordinate ethoxyl arm of the ligand is capable of accepting the proton from catechol, which mimics the function of Tyr447 in the protocatechuate 3,4-dioxygenase as an internal base. The spectrophotometric titration experiment indicates the relatively low demand of the external base (0.8 equiv based on Fe(3+)) for attaining the highest dioxygenase activity of complex 1. The reaction rate of the reactive intermediate [Fe(HL)(DBC)]+ with dioxygen is 0.38 M(-1) s(-1) determined by kinetic studies.     

A single tripodal ligand stabilizing three different oxidation states (II, III, and IV) of manganese

A series of mononuclear Mn(II), Mn(III), and Mn(IV) complexes was prepared using a single tripodal ligand (H(3)L). Addition of a cation (NH(4)(+), K(+), Na(+)) to [Mn(III)L] showed a pronounced effect on the redox potentials. Different variants of Jahn-Teller distortion, axial elongation and compression, were observed in the Mn(III) complexes.     

Synthesis, structures and catalytic properties of iron(III) complexes with asymmetric N-capped tripodal NO3 ligands and a pentadentate N2O3 ligand

A new family of N-capped tripodal NO(3) proligands N,N-bis(2-hydroxy-3,5-di-tert-butylbenzyl)-N-(2'-hydroxy-5'-R-phenyl)amine [H(3)(L(n))] [when R= Me, n = 1; R= (t)Bu, n = 2; R = Cl, n = 3] with different substituents in one of the aryl rings and N,N-bis(2-hydroxy-3-tert-butylbenzyl)-N-(2'-hydroxy-5'-methylphenyl)amine [H(3)(L(4))] were synthesised. The preparation of a new pentadentate proligand N-methyl-N,N',N'-tris(2-hydroxy-3,5-di-tert-butylbenzyl)ethane-1,2-diamine [H(3)(L(5))] with an N(2)O(3) donor set is also reported. Reaction of the proligands [H(3)(L(n))] (n = 1-4) with iron(iii) chloride in the presence of base (triethylamine) and 1-methylimidazole (1-Meim) as co-ligand led to the formation of iron complexes of the type [Fe(L(n))(1-Meim)] (n = 1-4) () respectively, while treatment of the trilithium salt of [H(3)(L(5))] with iron(iii) chloride afforded [Fe(L(5))] (). All complexes were structurally characterised by X-ray crystallography. In complexes , the ligands form five- and six-membered chelate rings with the iron centres which have distorted trigonal bipyramidal geometry with an N(2)O(3) coordination environment. Complex adopts a similar distorted trigonal bipyramidal geometry also with N(2)O(3) coordination around the iron centre. The catalytic activity of these iron complexes towards epoxidation of styrene was examined.     

Synthesis and characterization of tin(IV)/organotin(IV) complexes with 2-benzoylpyridine-N(4)-cyclohexylthiosemicarbazone [HBPCT]: X-ray crystal structure of [SnCl3(BPCT)]

Four new tin(IV)/organotin(IV) complexes, [SnCl₃(BPCT)] (2), [MeSnCl₂(BPCT)] (3), [Me₂SnCl(BPCT)] (4), and [Ph₂SnCl(BPCT)] (5), have been synthesized by the direct reaction of 2-benzoylpyridine-N(4)-cyclohexylthiosemicarbazone [HBPCT, (1)] and stannic chloride/organotin(IV) chloride(s) in absolute methanol under purified nitrogen. HBPCT and its tin(IV)/organotin(IV) complexes (2–5) were characterized by CHN analyses, molar conductivity, UV-Vis, FT-IR, and ¹H NMR spectral studies. In all the complexes, tin(IV) was coordinated via pyridine-N, azomethine-N, and thiolato-S from 1. The molecular structure of 2 has been determined by X-ray single-crystal diffraction analysis. Complex 2 is a monomer and the central tin(IV) is six-coordinate in a distorted octahedral geometry. The crystal system of 2 is monoclinic with space group P121/n1 and the unit cell dimensions are a?=?8.3564(3)?Å, b?=?23.1321(8)?Å, c?=?11.9984(4)?Å.     

Indazole complexes of diorganotin(IV) dihalides. The crystal structures of dichloro and dibromodimethylbis(indazole) tin(IV)

Reaction of indazole (HInd) with diorganotin(IV) dihalides yielded compounds of the type [SnR₂X₂(HInd)₂] (R = Me, Et, Bu and Ph; X = Cl, Br). The structures of the dihalodimethylbis(indazole)tin(IV) complexes were determined by X-ray crystallography. These are trans-octahedral centrosymmetric compounds with the following bond lengths (Å) around the tin atom: Sn-Cl 2.590(2), Sn-N 2.377(6), Sn-C 2.12(1) in the chloride; and Sn-Br 2.733(1), Sn-N 2.370(5) and Sn-C 2.12(1) in the bromide. Mössbauer and vibrational spectra suggest similar trans stereochemistry for the other complexes prepared. The behaviour of these compounds in solution was studied by conductimetry and NMR techniques.     

Pseudotetrahedral manganese complexes supported by the anionic tris(phosphino)borate ligand [PhBP(iPr)3

This paper presents aspects of the coordination chemistry of mono- and divalent manganese complexes supported by the anionic tris(phosphino)borate ligand, [PhBP(i)(Pr)3] (where [PhBP(i)(Pr)3] = [PhB(CH(2)P(i)Pr2)3]-). The Mn(II) halide complexes, [PhBP(i)(Pr)3]MnCl (1) and [PhBP(i)(Pr)3]MnI (2), have been characterized by X-ray diffraction, SQUID magnetometry, and EPR spectroscopy. Compound 2 serves as a precursor to a series of Mn azide, alkyl, and amide species: [PhBP(i)(Pr)3]Mn(N3) (3), [PhBP(i)(Pr)3]Mn(CH2Ph) (4), [PhBP(i)(Pr)3]Mn(Me) (5), [PhBP(i)(Pr)3]Mn(NH(2,6-(i)Pr2-C6H3)) (6), [PhBP(i)(Pr)3]Mn(dbabh) (7), and [PhBP(i)(Pr)3]Mn(1-Ph(isoindolate)) (8). The complexes 2-8 feature a divalent-metal center and are pseudotetrahedral. They collectively represent an uncommon structural motif for low-coordinate, polyphosphine-supported Mn complexes. Two Mn(I) species have also been prepared. These include the Tl-Mn adduct [PhBP(i)(Pr)3]Tl-MnBr(CO)4 (9) and the octahedral complex [PhBP(i)(Pr)3]Mn(CN(t)Bu)3 (10). Some of our initial synthetic efforts to generate [PhBP(i)(Pr)3]MnN(x) species are briefly described, as are DFT studies that probe the electronic viability of these types of multiply bonded target structures.     

Syntheses, crystal structures, and magnetic properties of novel manganese(II) complexes with flexible tripodal ligand 1,3,5-tris(imidazol-1-ylmethyl)-2,4,6-trimethylbenzene

Two novel metal-organic frameworks (MOFs)--[Mn(titmb)(N3)2] x 1.5H2O (1) and [Mn3(titmb)2(C2O4)3(H2O)] x 10H2O (2)--were obtained by reactions of the flexible tripodal ligand 1,3,5-tris(imidazol-1-ylmethyl)-2,4,6-trimethylbenzene (titmb) with Mn(OAc)2 x 4H2O, together with NaN3 and K2C2O4, respectively. The structures of these MOFs were established by single-crystal X-ray diffraction analysis. The crystal data for 1 were as follows: monoclinic, C2/c, a = 20.956(13) A, b = 9.884(6) A, c = 24.318(14) A, beta = 95.87(5) degrees, Z = 8. The crystal data for 2 were as follows: triclinic, P1, a = 12.400(9) A, b = 16.827(12) A, c = 17.196(11) A, alpha = 66.35(5), beta = 95.87(5) degrees, gamma = 71.03(6), Z = 2. Complex 1 is a novel noninterpenetrating three-dimensional (3D) framework, in which the azide ligand connects Mn(II) atoms in an end-to-end (EE) mode to give [Mn-N-N-N-]n infinite one-dimensional (1D) chains, and complex 2 has a two-dimensional (2D) network structure in which the Mn(II) ions are linked by the oxalate anions to form 1D [Mn(C2O4)]n chains. Each titmb in these two complexes connects three metal atoms and serves as a three-connecting ligand. The magnetic properties of 1 and 2 were investigated. The results showed that the antiferromagnetic interactions occurred between the Mn(II) ions linked by the azide ligands in complex 1, and those linked by the oxalate anions and the carboxylate in syn-anti coordination mode in complex 2. The entirely different structures of complexes 1 and 2, on one hand, indicate that the azide and the oxalate ligands affected the structures of MOFs greatly, and on the other hand, reveals the potential applications of MOFs with the azide and oxalate ligands, which are efficient magnetic couplers.     

Synthesis and X-ray crystal structures of two cobalt(III) complexes with Schiff bases

Two new mononuclear cobalt(III) complexes, [Co(MP)₂(N₃)] (I) and [Co(BP)₂]NO₃ · 2H₂O (II), where MP is 2-methoxy-6-[(2-morpholin-4-ylethylimino)methyl]phenolate and BP is 4-bromo-2-[(2-methylaminoethylimino)methyl]phenolate, were prepared and structurally characterized by physicochemical methods and single crystal X-ray diffraction. Both complexes crystallize in the monoclinic space group P2₁/c. For I: a = 10.3526(18), b = 25.371(4), c = 11.3585(19) Å, β = 101.529(8)°, V = 2923.1(8) ų, Z = 4; for II: a = 9.801(2), b = 27.183(3), c = 10.846(2) Å, β = 114.269(2)°, V = 2634.2(8) ų, Z = 4. An X-ray structural analysis indicates that in both complexes the Co atoms adopt octahedral coordination. The hindrance effects of the Schiff bases can influence the coordination of the secondary ligands such as azide.     

Determination of thiourea and some of its organic derivatives with sodium vanadate, hexacyanoferrate(III), Cerium(IV) sulphate, manganese(III) and manganese(IV)

The determination of thiourea and some of its organic derivatives with sodium vanadate, hexacyanoferrate(III), cerium(IV) sulphate, manganese(III) and manganese(IV) is described. A mixture of iodate and iodide is used as catalyst. Ferroin, N-phenylanthranilic acid and p-ethoxychrysoidine can be used as indicators.     

Synthesis and structure of dithizonato complexes of antimony(III), copper(II) and tin(IV)

In view of the important role of dithizone in trace metal analyses, new structural aspects and approaches used to probe metal complexes of dithizone are of interest. Three X-ray diffraction structures are reported, dichloridobis(dithizonato)tin(IV), dichlorido(dithizonato)antimony(III), and bis(dithizonato)copper(II). During synthesis of the tin complex, auto-oxidation of Sn^IICl₂ to Sn^IV occurred without chloride liberation. The Sb^III complex revealed a unique distorted see-saw geometry which is, as for the other complexes, predicted by DFT molecular orbital calculations. The computed products of the lowest energy reactions are in agreement with experimentally obtained reaction products, which, together with molecular orbital renderings serve as a tool toward prediction of modes of coordination in these complexes. The S–M–N bond angle in the five-membered coordination ring shows a linear relationship with the corresponding metal ionic radii.     

Trigonal-bipyramidal tin(IV) complexes containing tetradentate tripodal tristhiolatophosphine ligands: synthesis, characterization, crystal structure, and transmetalation reactions

The reactions of the lithium salts of the proligands P(C(6)H(4)-2-SH)(3) (P((H)SH)(3)), P(C(6)H(3)-3-SiMe(3)-2-SH)(3) (P((TMS)SH)(3)), and P(C(6)H(3)-5-Me-2-SH)(3) (P((Me)SH)(3)) with RSnCl(3) (R = Ph, Me, n-Bu), in THF at 0 degrees C, produced a series of trigonal-bipyramidal complexes of the type RSn(PS(3)). The crystal structures of PhSn(P(H)S(3)), PhSn(P(TMS)S(3)), and PhSn(P(Me)S(3)) reveal considerable distortion from local C(3v) symmetry for the Sn(PS(3)) group. Unique to PhSn(P(Me)S(3)) is the presence of intramolecular hydrogen bonding between one sulfur atom and an ortho H atom of the Ph group, creating a plane that includes this S atom and the corresponding C(6)H(3) ring, a phosphorus atom, and the PhSn group. An analysis of the (1)H, (13)C, and (31)P NMR data from a combination of HMQC, HMBC, 2-D COSY, and (1)H{(31)P} NMR studies reveals that in solution the Sn(PS(3)) groups exhibit local C(3v) symmetry, even at low temperature. Byproducts frequently found in the synthesis of the proligands and tin complexes, and subsequent reactions, result from the oxidation of the trianionic tristhiolatophosphine ligand. The crystal structure of one of these, [OP((H)S(3))](2), shows that the molecule contains two ligands joined by a S-S bond. Within each original ligand the remaining two sulfur atoms form a S-S bond, and each phosphorus atom is oxidized. PhSn(P(TMS)S(3)) reacted with 2 equiv of FeCl(3) in CH(2)Cl(2) to produce the iron(IV) complex FeCl(P(TMS)S(3)). FeCl(P(TMS)S(3)) decomposed in the presence of excess FeCl(3). Similar transmetalation reactions with FeCl(2) or [Fe(2)OCl(6)](2)(-) required the addition of ferrocenium ion to complete the oxidation of iron to 4+. RuCl(P(TMS)S(3)) was prepared by the reaction between PhSn(P(TMS)S(3)) and RuCl(2)(DMSO)(4) without the addition of an external oxidizing agent.     

Synthesis, crystal structures, and properties of oxovanadium(IV)-lanthanide(III) heteronuclear complexes

A new series of oxovanadium(IV)-lanthanide(III) heteronuclear complexes [Yb(H2O)8]2[(VO)2(TTHA)](3)21 H2O (1), {[Ho(H2O)7(VO)2(TTHA)][(VO)2(TTHA)](0.5)} 8.5 H2O (2), {[Gd(H2O)7(VO)2(TTHA)][(VO)2(TTHA)](0.5)}8.5 H2O (3), {[Eu(H2O)7][(VO)2(TTHA)](1.5)} 10.5 H2O (4), and [Pr2(H2O)6(SO4)2][(VO)2(TTHA)] (5) (H6TTHA=triethylenetetraaminehexaacetic acid) were prepared by using the bulky flexible organic acid H(6)TTHA as structure-directing agent. X-ray crystallographic studies reveal that they contain the same [(VO)2(TTHA)]2- unit as building block, but the Ln3+ ion lies in different coordination environments. Although the lanthanide ions always exhibit similar chemical behavior, the structures of the complexes are not homologous. Compound 1 is composed of a [Yb(H2O)8]3+ ion and a [(VO)2(TTHA)]2- ion. Compounds 2 and 3 are isomorphous; both contain a trinuclear [Ln(H2O)7(VO)2(TTHA)]+ (Ln=Ho for 2 and Gd for 3) ion and a [(VO)2(TTHA)]2- ion. Compound 4 is an extended one-dimensional chain, in which each Eu3+ ion links two [(VO)2(TTHA)]2- ions. For 5, the structure is further assembled into a three-dimensional network with an interesting framework topology comprising V2Pr2 and V4Pr2 heterometallic lattices. Moreover, 4 and 5 are the first oxovanadium(IV)-lanthanide(III) coordination polymers and thus enlarge the realm of 3d-4f complexes. The IR, UV/Vis, and EPR spectra and the magnetic properties of the heterometallic complexes were studied. Notably, 2 shows unusual ferromagnetic interactions between the VO2+ and Ho3+ ions.