Metal complexes of pyrimidine-derived ligands — Part 6. Bischelates of cobalt(II), nickel(II) and monochelates of copper(II) with 3, 5-dimethyl-1-(4′, 6′-dimethyl-2′-pyrimidyl)pyrazole,a potential antitumour agent

Summary Cobalt(II), nickel(II) and copper(II) complexes of 3, 5-dimethyl-1-(4, 6-dimethyl-2-pyrimidyl)pyrazole (DPymPz) have been synthesized and characterized. Magnetic and electronic spectral features show that both [M(DPymPz)₂X₂]·nH₂O [M=cobalt(II) or nickel(II), X=Cl, Br, I, SCN, NO₃, ClO₄ or BF₄ andn=0 or 2] and [Cu(DPymPz)X₂(H₂O)₂] (X=Cl, Br or SCN) are essentially octahedral species. The i.r. spectra indicate that DPymPz is a neutral bidentate ligand being the pyrazolyl and one pyrimidyl ring nitrogen. The X is bonded to the central metal ion in a majority of the complexes.Part 5: N. Saha and D. Mukherjee,Polyhedron,5, 1317 (1986).     

Copper(II) α-hydroxycarboxylate complexes of bis(2-pyridylcarbonyl)amine ligand: From mononuclear complex to one-dimensional coordination polymer

The coordination geometry and supramolecular structures of three copper(II) complexes of two α-hydroxycarboxylates and one α-methoxycarboxylate with nitrogen donor co-ligands are discussed. The complexes have been characterized by elemental analysis, ESI-MS, IR and electronic spectroscopy, thermogravimetric analysis and magnetic measurements. The X-ray structure analysis of all the complexes, namely [(BPCA)Cu^II(MA)] (1), [(BPCA)Cu^II(MPA)(H₂O)] (2) and [(BPCA)Cu^II(BA)]_n (3), where BPCA = bis(2-pyridylcarbonyl)amidate, MA = racemic mandelate, MPA = racemic α-methoxy phenylacetate and BA = benzilate anion, shows the copper(II) ion in a distorted square-pyramidal geometry. In 1 the mandelate anion is coordinated to the copper(II) center in a bidentate fashion while in 2 the α-methoxycarboxylate is monodentate. In both cases a one-dimensional supramolecular array is formed through hydrogen bonds: the mononuclear units are directly connected in 1 by the MA hydroxyl group, whereas in 2 is the coordinated water that operates as H donor towards the MPA carboxylate group and the BPCA carbonyl oxygens of nearby complexes. In 3 the benzilate anion, acting as bridging ligand between copper ions, gives rise to a one-dimensional coordination polymer. In the latter, intra- and inter-chain π?π stacking interactions between pyridines and one phenyl ring of benzilate anions are observed in the packing.     

Cobalt(II), nickel(II) and copper(II) complexes of 5-(2-carboxyphenylazo)-2-thiohydantoin

A new series of hexacoordinate cobalt(II), nickel(II) and copper(II) complexes of 5-(2-carboxyphenylazo)-2-thiohydantoin HL having formulae [LM(OAc)(H₂O)₂] · nH₂O (M = Co^II, Cu^II and Ni^II), [LMCl(H₂O)₂] · nH₂O (M = Co^II and Ni^II), [LCuCl(H₂O)]₂ · 2H₂O, [LCu(H₂O)₃](ClO₄) and [LCu(HSO₄)(H₂O)₂] were isolated and characterized by elemental analyses, molar conductivities and magnetic susceptibilities, and by i.r., electronic and e.s.r. spectral measurements, as well as by thermal (t.g. and d.t.g.) analyses. The i.r. spectra indicate that the ligand HL behaves as a monobasic tridentate towards the three divalent metal ions via an azo-N, carboxylate-O and thiohydantoin-O atom. The magnetic moments and electronic spectral data suggest an octahedral geometry for Co^II complexes, distorted octahedral geometry for both Ni^II and Cu^II complexes with a dimeric structure for [LCuCl(H₂O)]₂ · 2H₂O through bridged chloro ligands. The X-band e.s.r. spectra reveal an axial symmetry for the copper(II) complexes with unsymmetrical M_s = ± 1 signal and G-parameter less than four for the dimeric [LCuCl(H₂O)]₂ · 2H₂O. The thermogravimetry (t.g. and d.t.g.) of some complexes were studied; the order and kinetic parameters of their thermal degradation were determined by applying Coats–Redfern method and discussed.     

H2O soluble ternary complexes of divalent transition metal ions with AN-(2-acetamido)iminodiacetic acid and heterocyclic diimines

Summary H₂O soluble mixed ligand complexes of the type [M-(ADA)B·H₂O] where M = Ni^II or Cu^II; [ADA]^2- = divalent anion of N-(2-acetamido)iminodiacetic acid, B = heterocyclic diimine (2,2'-bipyridyl or 1,10-phenanthroline), were prepared and characterized by elemental and thermal analyses, i.r. and electronic spectra, as well as conductivity measurements. Formation constants for the 111 ternary cobalt(II), nickel(II) and copper(II) complexes formed in solution were determined potentiometrically at 24 °C and = 0.1mol dm^-3(KNO₃).     

Oxidative Dehydrogenation of Cu(II) Complexes with N-Aryl-N-2-hydroxybenzyl- and N-Aryl-N-2-hydroxynaphthylmethyleneamine Derivatives

The reactions of Cu²⁺, Co²⁺, and Ni²⁺ ions with N-phenyl-N-2-hydroxybenzyl- and N-phenyl-N-2-hydroxynaphthylmethyleneamine derivatives (HL ⁿ , n = 1–8) produced from the derivatives of aniline and aromatic -hydroxyaldehydes are studied. Among the ions studied, only Cu²⁺ forms stable complexes Cu(L ⁿ )₂ · 2H₂O. The structures of the synthesized compounds are studied by IR, UV, and EPR spectroscopies and differential thermal analysis. The magnetic moments of the Cu(L ⁿ )₂ · 2H₂O complexes are very small and range within 0.43–1.19 _B, depending on the ligand structure, which indicates a strong antiferromagnetic interaction between the Cu²⁺ ions. The temperature dependence of the magnetic susceptibility measured for the Cu(L³)₂ · 2H₂O complex (where HL³ is N-4-methoxyphenyl-N-2-hydroxybenzylamine) is closest to the theoretical curve calculated for the binuclear Cu(II) complexes connected by the intermolecular exchange interaction. The Cu(II) complexes with HL ⁿ are shown to undergo oxidative dehydrogenation to form the corresponding metal salicyl-aldiminates. This reaction can occur on heating in the absence of oxygen and is accompanied by the Cu²⁺ Cu⁺ transition.     

Metal complexes of sulfur-nitrogen chelating agents. Part 12. The chemistry of nickel(II), palladium(II), cobalt(II) and copper(II) complexes of N2S2 and N3S2 donor systems

Summary Nickel(II), palladium(II), cobalt(II) and copper(II) complexes of the ligandN,N-1,2-propane-bis(methyl 2-amino-cyclopent-1-ene-dithiocarboxylate) (H₂L¹),N,N-1,3-propane-bis(methyl 2-aminocyclopent-1-ene-dithiocarboxylate) (H₂L²) andN,N-[bis(methyl 2-aminocyclopent-1-ene-dithiocarboxylate)] diethylenetriamine (H₂L³) have been synthesised. Both H₂L¹ and H₂L² form complexes of the type ML, and all but the copper(II) complexes, are square planar. In the copper(II) complexes tetrahedral distortion is significantly more with CuL². From H₂L³ square planar complexes of the type [M(HL³)X] (M=Ni, X=Cl, Br, I or SCN; M=Pd, X=Cl or Br) have been obtained in which the donor unit involved is N₂SX. The composition of the cobalt(II) and copper(II) complexes is [M(H₂L³)X₂] (X=Cl or Br) which contain the chromophore [MN₃X₂].     

Mono and dinuclear copper(II) complexes of 2,4,6-tris(2-pyridyl)-1, 3,5-triazine and halide or pseudohalide ions: Synthesis and spectral studies

Summary By inhibiting the copper(II) assisted TPT (TPT = 2,4,6-tris(2-pyridyl)-1,3,5-triazine) hydrolysis, monomeric and dimeric copper(II) complexes having as general formulae Cu(TPT)X, · nH₂O (X = Cl, Br, NCS, NCO or N₃) and [Cu(TPT)X]₂(PF₆)₂ · nH₂O (X = Cl, Br, NCS or N₃) have been synthesized and characterized by i.r., electronic and e.p.r. spectra, x-ray powder diffraction and analytical data. Spectroscopic results indicate five-coordinate geometry around the copper(II) ion, intermediate between trigonal-bipyramid and square-pyramid structures. The half-field absorption in the M_S = 2 region of powdered X-band e.p.r. spectra has been observed for the dimeric species.     

Über Synthesen der Verbindungen von Mn,Fe, Co,Ni, Cu und Zn mit Hydrazidokohlensäure

Zusammenfassung Die Synthesen und einige Eigenschaften der Verbindungen von zweiwertigem Mn, Cu, Fe, Co, Ni und Zn mit Hydrazidokohlensäure werden beschrieben. Die Verbindungen von Fe, Co, Ni und Zn sind Hydrazinium-hydrazidocarbonato-metallate(II) der allgemeinen Formel N₂H₅[Me ^II(N₂H₃COO)₃]·H₂O, die von Mn und Cu sind aber einfache Hydrazido-carbonate der FormelMe ^II(N₂H₃COO)₂·n H₂O. Die Ergebnisse magnetochemischer Messungen sowie der orientierender Messungen der thermischen Eigenschaften werden angegeben.

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The syntheses and some properties of the compounds of bivalent Mn, Fe, Co, Ni, Cu and Zn with hydrazido-carbonic acid are described. The compounds of Fe, Co, Ni and Zn are hydrazinium hydrazido-carbonato-metallates(II) with the formula N₂H₅[Me ^II(N₂H₃COO)₃]·H₂O. The compounds of Mn and Cu are hydrazido-carbonatesMe ^II(N₂H₃COO)₂·n H₂O. The results of magnetic and preliminary measurements of thermal properties are given.

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J. Slivnik, A. malc, B. Sedej undM. Vilhar, Vestnik SKD (Bull. Soc. chim. Slovène)11, 53 (1964).     

Synergic effect of triphenylphosphine oxide (TPPO) on the extraction of Hg(II), Se(IV), Co(II) and Mn(II) with fluorinated pyrazolone (HPMTFP)

Extraction of Hg(II), Se(IV), Mn(II) and Co(II) has been carried out with 1-phenyl-3-methyl-4-trifluoroacetyl-2-pyrazolin-5-one (HPMTFP) and triphenylphosphine oxide (TPPO) into chloroform from pH 1–10. Quantitative extraction of Hg(II), Mn(II) and Co(II) at pH 4 with equimolar 0.05M (PMTFP+TPPO) in chloroform was observed. Se(IV) remains unextracted at this pH range. The stoichiometric composition of the extracted complexes M(PMTFP)₂·nH₂O (M=Mn, Hg), M(PMTFP)₂·2TPPO (M=Mn and Co) and Co(PMTFP)₂·TPPO·H₂O at less than 0.1M TPPO has been established. The formation constantsK _m,0 andK _m,n and stability constants _m,n have been computed. The analytical method developed was applied to the IAEA standard reference material (SRM) potato fluor V-4 for the determination of these elements using NAA technique.     

Coordination Compounds of Cobalt, Nickel, and Copper with Isonitrosoacetone Benzoylhydrazone

Benzoylhydrazine, isonitrosoacetone react in ethanol with cobalt, nickel, copper halides andacetates to give the coordination compounds MX₂(HL) · nH₂O, MX₂(HL)₂ · nH₂O, and ML₂ · nH₂O [M = Co,Ni, Cu; X = Cl, Br; HL = C6H5C(O)NHNC(CH3)CHNOH; n = 1-4]. The same reactions performed in the presence of sodium acetate and pyridine (pH 7-8) yield the complexes MLCl · nH₂O and MPy₂LCl ·nH₂O (n = 1-4). All the complexes have a pseudooctahedral coordination geometry. The hydrazone HL behaves as a tridentate O,N,N-donor ligand. Thermolysis of the substances involves dehydration (70-90°C), deaquation (155-170°C) or deamination (175-195°C), and complete thermal decomposition (285-360°C).     

Crystal structure and magnetic properties of a new polymer [Cu(PzdcH)2·2H2O]n

Two different products are obtained when 2,3-pyrazinedicarboxylic acid (PzdcH₂) reacts separately with two copper(II) salts: Cu(OAc)₂ and CuCl₂. One product is a mononuclear Cu^II complex Cu(PzdcH)₂·2H₂O, the other is a linear polymeric copper(II) complex [Cu(PzdcH)₂·2H₂O]_n, whose structure has been determined by X-ray diffraction at room temperature. The polymeric complex is composed of copper(II) ions, PzdcH^- anions and crystal water molecules. The Cu(1) atom is located in elongated octahedral coordination environment with six donor atoms: O(1), N(1), O(1a), N(1a), O(3b) and O(3c) from four different PzdcH^- anions. The two oxygen atoms O(3b) and O(3c) come from the carboxylic acid group of the PzdcH^- anion of the upper and lower layers, so that an infinite chain constitutes the crystal lattice. There are very strong hydrogen bond interactions between chains which lead to a three-dimensional structure. The magnetic susceptibility of the polymeric complex [Cu(PzdcH)₂·2H₂O]_n has been determined in the 1.5–300K range. A study of magnetic properties shows that a weak antiferromagnetic interaction exists between two copper(II) ions.     

Synthesis, spectral characterization and crystal structure of copper(II) complexes of 2-benzoylpyridine-N(4)-phenylsemicarbazone

An interesting series of nine new copper(II) complexes [Cu₂L₂(OAc)₂]·H₂O (1), [CuLNCS]·½H₂O (2), [CuLNO₃]·½H₂O (3), [Cu(HL)Cl₂]·H₂O (4), [Cu₂(HL)₂(SO₄)₂]·4H₂O (5), [CuLClO₄]·½H₂O (6), [CuLBr]·2H₂O (7), [CuL₂]·H₂O (8) and [CuLN₃]·CH₃OH (9) of 2-benzoylpyridine-N(4)-phenyl semicarbazone (HL) have been synthesized and physico-chemically characterized. The tridentate character of the semicarbazone is inferred from IR spectra. Based on the EPR studies, spin Hamiltonian and bonding parameters have been calculated. The g values, calculated for all the complexes in frozen DMF, indicate the presence of the unpaired electron in the d_x²-y² orbital. The structure of the compound, [Cu₂L₂(OAc)₂] (1a) has been resolved using single crystal X-ray diffraction studies. The crystal structure revealed monoclinic space group P2₁/n. The coordination geometry about the copper(II) in 1a is distorted square pyramidal with one pyridine nitrogen atom, the imino nitrogen, enolate oxygen and acetate oxygen in the basal plane, an acetate oxygen form adjacent moiety occupies the apical position, serving as a bridge to form a centrosymmetric dimeric structure.     

Oxamidato complexes. Part 4. Electrochemical study of the copper(III)/copper(II) couple in monomeric N,N′-bis(substituent)oxamidatocopper(II) complexes

Summary The electrochemical behaviour of a series of monomeric N,N-bis(substituent)oxamidato copper(II) complexes of formula Na₂[Cu(3,5,3,5-X₄obbz)]·4H₂O [X = Cl (1), Br (2), I (3) and obbz = oxamidobis(benzoato)], Na₂-[Cu(obbz)]·4H₂O (4), Na₂[Cu(5,5-Me₂obbz)]·4H₂O (5), Na₂[Cu(4,5,4,5-(MeO)₄obbz)]·4H₂O(6),Na₂[Cu(obp)]· 3.5H₂O (7) (obp = oxamidobis(propionato)) and Na₂[Cu(pba)]·6H₂O (8), [pba = propylenebis(oxamate)] has been investigated by cyclic voltammetry, rotating disk electrode and coulometry in water and dimethylsulphoxide (dmso) solutions. NaNO₃ (0.1 M) and n-Bu₄NPF₆ (0.1 M) were used as supporting electrolytes in H₂O and dmso respectively, all solutions being thermostatted at 25 °C. In aqueous solution, the complexes show an oxidation peak ranging from 1.19 to 0.86 V (values referred to the s.c.e.), the corresponding reduction being unobserved, even at high scan rates. In dmso, all the complexes exhibit only one oxidation peak ranging from 0.86 to 0.51 V, the corresponding reduction being observed for all of them except for (3). The oxidation potentials are strongly dependent upon the nature of the N,N-substituent of the oxamide. The copper(III)-assisted hydrolysis of the oxamidate ligand is analysed in terms of the lack of planarity of the oxamidate ligand induced by the steric effect of the halogen substituent in the 3-position on the phenyl rings. The influence of the nature of the solvent was also studied.     

Synthesis and spectral studies of copper(II), nickel(II), cobalt(II) and vanadyl(II) complexes of tridentate Schiff bases of 1,2,3,5,6,7,8,8a-octahydro-3-oxo-N,1-diphenyl-5-(phenylmethylene)-2-naphthalenecarboxamide

Summary Metal(II) chelates of Schiff bases derived from the condensation of 1,2,3,5,6,7,8,8a-octahydro-3-oxo-N,1-diphenyl-5-(phenylmethylene)-2-naphthalenecarboxamide with o-aminophenol (KAAP), o-aminothiophenol (KAAT) or o-aminobenzoic acid (KAAB) have been prepared and characterized. The complexes are of the type [M(N₂X)]₂ for M = Cu^II and M(NX)₂·nH₂O for M = Ni^II, Co^II and VO^II (X = phenolic oxygen, thiophenolic sulphur or carboxylic oxygen; n = 0 or 2). Conductivity data indicate that the complexes are non-ionic. The Schiff bases behave as dibasic tridentate ligands in their copper(II) complexes and as monobasic bidentate ligands in their nickel(II), cobalt(II) and vanadyl(II) complexes. The subnormal magnetic moments of the copper(II) complexes are ascribed to an antiferromagnetic exchange interaction arising from dimerization. Nickel(II) and cobalt(II) complexes are trans octahedral whereas vanadyl(II) complexes are square pyramidal     

Restricting the versatile metal-binding behaviour of adenine by using deaza-purine ligands in mixed-ligand copper(II) complexes

In order to deepen our understanding of the versatile behaviour of adenine (Hade) as ligand, we have synthesized four novel ternary copper(II) complexes having two deazaadenine ligands, namely 4-azabenzimidazole (H4abim) or 7-azaindole (H7azain) as N1,N6-dideazaadenine or N1,N6,N7-trideazaadenine, respectively. The related compounds were studied by thermal, spectral and single crystal X-ray diffraction methods. In [Cu(NBzIDA)(H4abim)]_n (1) the recognition between H4abim and the (N-benzyliminodiacetate)-copper(II) chelate only displays the formation of the Cu–N7(purine-like) bond, in contrast to Hade behaviour in [Cu(NBzIDA-like)(Hade)(H₂O)]·H₂O (Cu–N3(Hade) bond reinforced by N9–H···O(IDA-like) interaction). In [Cu(EIDA)(H7azain)(H₂O)] (2, EIDA = N-ethyliminodiacetate ligand), [Cu(NBzIDA)(H7azain)(H₂O)] (3) and [Cu(μ₂-SO₄)(H7azain)₂(H₂O)₂]_n (4), H7azain binds Cu(II) centre by the Cu–N3(purine-like) bond, reinforced by a N9–H···O(IDA-like or sulfate) intra-molecular interligand interaction.     

Synthesis,electrochemical and e.p.r. spectral studies of binuclear copper(II) complexes with new pentadentate L-proline-based binucleating ligands

The synthesis, reduction, optical and e.p.r. spectral properties of a series of new binuclear copper(II) complexes, containing bridging moieties (OH^–, MeCO₂ ^–, NO₂ ^–, and N₃ ^–), with new proline-based binuclear pentadentate Mannich base ligands is described. The ligands are: 2,6-bis[(prolin-1-yl)methyl]4-bromophenol [H₃L¹], 2,6-bis[(prolin-1-yl)methyl]4-t-butylphenol [H₃L²] and 2,6-bis[(prolin-1-yl)methyl]4-methoxyphenol [H₃L³]. The exogenous bridging complexes thus prepared were hydroxo: [Cu₂L¹(OH)(H₂O)₂] · H₂O (1a), [Cu₂L²(OH)(H₂O)₂] · H₂O (1b), [Cu₂L³(OH)(H₂O)₂] · H₂O (1c), acetato [Cu₂L¹(OAc)] · H₂O (2a), [Cu₂L²(OAc)] · H₂O (2b), [Cu₂L³(OAc)] · H₂O (2c), nitrito [Cu₂L¹(NO₂)(H₂O)₂] · H₂O (3a), [Cu₂L²(NO₂)(H₂O)₂] · H₂O (3b), [Cu₂L³(NO₂)(H₂O)₂] · H₂O (3c) and azido [Cu₂L¹(N₃)(H₂O)₂] · H₂O (4a), [Cu₂L²(N₃)(H₂O)₂] · H₂O (4b) and [Cu₂L³(N₃)(H₂O)₂] · H₂O (4c). The complexes were characterized by elemental analysis and by spectroscopy. They exhibit resolved copper hyperfine e.p.r. spectra at room temperature, indicating the presence of weak antiferromagnetic coupling between the copper atoms. The strength of the antiferromagnetic coupling lies in the order: NO₂ N₃ OH OAc. Cyclic voltammetry revealed the presence of two redox couples Cu^IICu^II Cu^IICu^I Cu^ICu^I. The conproportionality constant K _con for the mixed valent Cu^IICu^I species for all the complexes have been determined electrochemically.     

Synthesis,spectroscopy and thermal analysis of nickel(II), palladium(II) and copper(II) complexes with N,N′-bis(2-hydroxyethyl)-oxamide

Summary The new complexes K₂[Ni(H₂heo)₂]·3H₂O, K₂[Pd-(H₂heo)₂], K₂[Cu(heo)]·3H₂O and [Cu₂(heo)·2H₂O] {heo = [(CONCH₂CH₂O)₂]^4-} were prepared and characterized by chemical analyses, conductivity measurements, thermogravimetry, magnetic susceptibility and i.r. and u.v. spectroscopy.Monomeric square planar structures with MN₄ coordination spheres are found for the nickel and palladium complex anions.For copper, two different complexes were identified. In slightly alkaline media, a green insoluble nonelectrolyte [Cu₂(heo)·2H₂O] was prepared; the two copper(II) centres are bridged by the tetra-deprotonated ligand in a trans-planar configuration with the H₂O molecules strongly coordinated to the copper(II). The copper(II) monomer has been prepared in strong alkaline media, this anion also contains the tetra-deprotonated ligand in a planar trans form.     

Synthesis, characterization and antitumour properties of metal(II) solid complexes with Morin

Summary Six metal(II) complexes with Morin ML₂·nH₂O [L = Morin(2-OH group deprotonated); M = Mn, Co, Ni, Cu, Zn, or Cd; n = 2 or 3] have been synthesized and characterized by elemental analysis, molar conductance, i.r., ¹H-n.m.r., t.g.-d.t.a and u.v.-vis. spectroscopic techniques and by fluorescence analysis. Comparative antitumour activities of Morin·2H₂O and two complexes [ZnL₂·3H₂O and CuL₂·2H₂O] were tested by in vitro screening. The results show that the inhibitory ratio of complexes against the tested tumour cells was higher than that of Morin.     

Solvothermal synthesis and crystal structures of two new copper(II) terephthalates

Two new copper(II) complexes, [Cu₂(bipy)₂(H₂O)₃(tp)(NO₃)](NO₃) · H₂O (1) and [Cu₂(bipy)₂(tp)₂(H₂O)] _n (2), (tp = terephthalato, bipy = 2,2-bipyridine), have been synthesized and their crystal structures determined by single-crystal X-ray diffraction methods. Complex (1) contains a non-coordinated nitrate anion and an asymmetric binuclear cation in which each copper ion has a distorted square pyramidal coordination geometry with the axial Cu—O distance elongated. The crystal structure of (2) features a zigzag 1D polymeric chain along the diagonal axis of the (0 0 1) plane. Tp adopts two types of coordination mode. In the first mode, both carboxylate groups are unidentate, as in complex (1). In addition to the first mode, the tp ligand in complex (2) also adopts the second coordination mode, in which one carboxylate group is unidentate and the other is bidentately chelating with a copper(II) ion. The magnetic properties of complex (2) have also been studied.     

Synthesis,Spectroscopic Characterization,and Crystal Structure of the Lanthanide(III) Complex [Ce(hydrazone)<Subscript>2</Subscript>(NO<Subscript>3</Subscript>)(NCS)(H<Subscript>2</Subscript>O)]NO<Subscript>3</Subscript>·2.35H<Subscript>2</Subscript>O

Three new lanthanide(III) complexes of the type [Ln(PBH)₂(NO3)(NCS)(H₂O)]NO₃·nH₂O (PBH = 2-pyridinecarboxaldehyde benzoyl-hydrazone) have been prepared from the complexes [Ln(PBH)₂(NO₃)₃]·CH₃COCH₃·2H₂O by anion metathesis reaction and studied by elemental analyses, IR and UV–Vis spectra. The crystal structure of the [Ce(PBH)₂(NO₃)(NCS)(H₂O)]NO₃2.35H₂O complex was determined by X-ray diffraction. The crystals of the compound isothiocyanato-nitrato-aquo-bis[N-(2-pyridinylmethylene)-N-benzoyl-hydrazino]-cerium(III) nitrate 2.35 hydrate are monoclinic with crystallographic P2₁ n symmetry. The coordination sphere consists of two tridentate 2-pyridinecarboxaldehyde benzoylhydrazone, one bidentate nitrate, one isothiocyanate, and one water molecule as ligands. The coordination polyhedron around the cerium atom can be described as a distorted bicapped square antiprism. The coordination of the hydrazone ligand to the metal atom is accomplished through the pyridine nitrogen, the azomethine nitrogen, and the carbonyl oxygen.