Synthesis,characterization, and biological activities of macrocyclic polyamine complexes

Two new dinuclear macrocyclic complexes, [Ni₂L¹(OAc)]·ClO₄ (1) and [Co₂L²(OAc)]·1.5(ClO₄)·0.5Na·2(CH₃OH) (2) (where H₂L¹ and H₂L² are the condensation products of N,N-bis(3-aminopropyl)-4-methoxybenzylamine with 2,6-diformyl-4-brominephenol and 2,6-diformyl-4-methylphenol in the presence of metal ions, respectively) have been synthesized and characterized by infrared spectra, elemental analysis, electrospray mass spectra, and X-ray single crystal diffraction. The interactions of the complexes with CT-DNA have been measured by UV-absorption titrations and fluorescence quenching experiments.     

Binuclear and polynuclear transition metal complexes with macrocyclic ligands. 4. New polydentate azomethine ligands based on 2,5-diformylpyrrole and 2,6-diformylpyridine

The reactions of 2,5-diformylpyrrole (1) and 2,6-diformylpyridine (2) with propane-1,3-diamine afforded new macrocyclic Schiff"s bases 5 and 6, respectively. Their structures were established by NMR spectroscopy and mass spectrometry. Binuclear copper(ii) and nickel(ii) complexes with ligand 5 were synthesized. Pentadentate Schiff"s base, viz., 2,6-bis[(2-aminophenylimino)methyl]pyridine, was prepared by demetallation of its complex with Cd(ClO₄)₂ using Na₂S. In solutions, the latter Schiff"s base is quantitatively transformed into 2,6-bis(benzoimidazolyl)pyridine under the action of atmospheric oxygen or other mild oxidizing agents.     

Synthesis,crystal structure and catalytic performance of bis (imino)pyridyl nickel complexes

Two new Ni(II) complexes of 2,6-bis[1-(2,6-diethylphenylimino)ethyl]pyridine (L¹), 2,6-bis[1-(4-methylphenylimino)ethyl]pyridine (L² ) have been synthesized and structurally characterized. Complex Ni(L¹)Cl₂?·?CH₃CN (1), exhibits a distorted trigonal bipyramidal geometry, whereas complex Ni(L¹)(CH₃CN)Cl₂ (2), is six-coordinate with a geometry that can best be described as distorted octahedral. The catalytic activities of complexes 1, 2, Ni{2,6-bis[1-(2,6-diisopropyl-phenylimino)ethyl]pyridine} Cl₂?·?CH₃CN (3), and Ni{2,6-bis[1-(2,6-dimethylphenylimino) ethyl]pyridine}Cl₂?·?CH₃CN (4), for ethylene polymerization were studied under activation with MAO.     

Synthesis,crystal structures and toxicity of bicadmium(ii) complexes with macrocyclic,hexaaza-bearing,hydroxyethyl pendants

Three bicadmium(II) complexes with hydroxyethyl pendants were synthesized by [2?+?2] Schiff-base condensation of 2-[bis(2-aminoethyl)amino]ethanol with sodium 2,6-diformyl-4-R-phenolate (for Complex 1, R?=?F; Complex 2, R?=?Cl; Complex 3, R?=?CH₃) in the presence of Cd²⁺. Crystals of 1 were monoclinic, space group P2₁/c, with a?=?16.251(9), b?=?21.424(11), c?=?12.994(7)?Å and β?=?106.622(9)°. Both Cd(II) atoms were heptacoordinated with monocapped-octahedral geometry. Complex 3 crystals were isolated as triclinic, space group P?1 with α?=?15.502(4), b?=?16.060(4), c?=?16.642(5)?Å and α?=?68.813(4), β?=?80.836(4), γ?= 86.551(4)°. The coordination number and coordination geometry of the Cd ion in one cationic unit of 3 are similar to that of 1, while in the other cationic unit, one Cd atom is N₃O₄ heptacoordinated and the other Cd atom has an N₃O₃ coordination environment and possesses a distorted octahedral geometry. The toxicity of these complexes was evaluated by testing antimicrobial activity against bacterial strands.     

New polydentate macrocyclic ligands of hybrid amine-imine and amide-imine types as artificial anion receptors. Synthesis and study of anion binding

Three new macrocyclic Schiff bases containing an amine or amide structural fragment along with imine groups were synthesized by condensation of 2,6-bis(2-aminophenyliminomethyl)pyridine (1) and N, N’-bis(2-aminophenyl)pyridine-2,6-dicarboxamide (2) with 2,5-diformylpyrrole (₃) and 2,2-bis(5-formylpyrrol-2-yl)propane (4). The reaction of compound 1 with 3 proceeds abnormally and is accompanied by redox disproportionation of compound 1 in the first step. The structure of the macrocyclic product of this reaction was established by X-ray diffraction analysis. Spectrophotometric titration showed that hybrid macrocycle 10, which was prepared by condensation of compound 2 with 4, possesses the properties of an anion receptor and selectively binds hydrosulfate and dihydrophosphate anions in the presence of bromide and nitrate anions. The structures of 10 and its adduct with the hydrosulfate anion were calculated by density functional theory.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 161–168, January, 2005.     

Synthesis,structure and catalytic properties of new half-titanocene complexes bearing substituted cyclopentadienyl and aryloxide ligands

New cyclopentadienyltitanium aryloxide complexes, 1-phenyl-2,3,4,5-Me4CpTi(O-2,6-ⁱPr₂-4-ⁿBu-C₆H₂)Cl₂ (1) and [4,4′-biphenyl-(2,3,4,5-Me₄Cp)₂][Ti(O-2,6-ⁱPr₂-4-ⁿBu-C₆H₂)Cl₂]₂ (2), have been prepared by treatment of cyclopentadienyltitanium trichloride complexes [PhMe₄CpTiCl₃ and 4,4′-biphenyl-(Me₄CpTiCl₃)₂] with 1 or 2 equiv of lithium salt of 2,6-di-isopropyl-4-butylphenol. Complexes 1 and 2 have been characterized by elemental analysis, ¹H and ¹³C NMR spectroscopy. The molecular structure of 1 has been determined by single-crystal X-ray diffraction. Upon activation with ⁱBu₃Al and Ph₃CB(C₆F₅)₄, 1 and 2 both exhibit good catalytic activity for ethylene polymerization, producing polyethylene with moderate molecular weight and melting point.     

Chromium(III) complexes bearing bis(benzotriazolyl)pyridine ligands: synthesis,characterization and ethylene polymerization behavior

Reaction of benzotriazole with 2,6-bis(bromomethyl)pyridine and 2,6-pyridinedicarbonyl dichloride yields the tridentate ligands 2,6-bis(benzotriazol-1-ylmethyl)pyridine (1) and 2,6-bis(benzotriazol-1-ylcarbonyl) pyridine (2). The molecular structures of the ligands were determined by single-crystal X-ray diffraction. These ligands react with CrCl₃(THF)₃ in THF to form neutral complexes, [CrCl₃{2,6-bis(benzotriazolyl)pyridine-N,N,N}] (3, 4), which are isolated in high yields as air stable green solids and characterized by mass spectra (ESI), FTIR spectroscopy, UV–Visible, thermogravimetric analysis (TGA), and magnetic measurements. After reaction with methylaluminoxane (MAO), the chromium(III) complexes are active in the polymerization of ethylene showing a bimodal molecular weight distribution. A DFT computational investigation of the polymerization reaction mechanism shows that the most likely reaction pathway originates from the mer configuration when the spacer is CH₂ (complex 3) and from the fac configuration when the spacer is CO (complex 4).     

Synthesis and crystal structure of Mn(II) complexes with novel macrocyclic Schiff-base ligands containing piperazine moiety

A series of Mn(II) macrocyclic Schiff-base complexes [MnLⁿCl]⁺ (n = 1–4) have been prepared via the Mn(II) templated [1+1] cyclocondensation of 2,6-diacetylpyridine or 2,6-pyridinedicarbaldehyde with the symmetrical 1,4-bis(3-aminopropyl)piperazine or the novel asymmetrical N,N′(2-aminoethyl)(3-aminopropyl)piperazine linear amines containing piperazine moiety. The complexes have been characterized by elemental analyses, IR, FAB-MS, magnetic studies and conductivity measurements. The crystal structure of [MnL²(CH₃OH)Cl](ClO₄) and [MnL⁴Cl](PF₆) complexes have also been determined showing the metal ion in a N₄OCl pentagonal bipyramidal or N₄Cl highly distorted octahedral geometry, respectively.     

Synthesis,characterization, and fluorescence properties of dinuclear cadmium(II) complexes

Four dinuclear cadmium(II) complexes, [Cd₂(L¹)(μ₂-Cl)Cl₂] (1), [Cd₂(L²)(μ₂-Cl)Cl₂] (2), [Cd₂(L³)(μ₂-Cl)Cl₂] (3), and [Cd₂(L⁴)₃ClO₄] (4), where HL¹ = 4-methyl-2,6-bis(1-(2-piperidinoethyl)iminomethyl)-phenol, HL² = 4-methyl-2,6-bis(1-(2-pyrrolidinoethyl)iminomethyl)-phenol, HL³ = 4-methyl-2,6-bis(1-(2-morpholinoethyl)iminomethyl)-phenol and HL⁴ = 4-methyl-2,6-bis(cyclohexylmethyl)iminomethyl)-phenol, were synthesized. They were characterized by elemental analysis, FT-IR, UV–Vis, fluorescence and electronspray ionization mass spectroscopy. Complexes 1 and 4 were also characterized by single crystal X-ray analysis. The cadmiums atoms in 1 are linked by μ₂-chloride in a distorted square pyramidal geometry, whereas cadmium atom in 4 is in a distorted octahedral environment. The complexes show emission bands around 500 nm with excitation at 395 nm.     

Ethylene/1-hexene copolymerization by salicylaldiminato vanadium(III) complexes activated with diethylaluminum chloride

Mono salicylaldiminato vanadium（Ⅲ） complexes（1a-1f）[RN = CH（ArO）]VCl₂（THF）₂（Ar = C₆H₄（1a-1e）,R = Ph,1a;R = p-CF₃Ph,1b;R = 2,6-Me₂Ph,1c;R = 2,6-iPr₂Ph,1d;R = cyclohexyl,1e;Ar = C₆H₂tBu₂（2,4）,R = 2,6-iPr₂Ph, 1f） and bis（salicylaldiminato） vanadium（Ⅲ） complexes（2a-2f）[RN = CH（ArO）]₂VCl（THF）_x（Ar = C₆H₄（2a-2e）,x = 1 （2a-2e）,R = Ph,2a;R =p-CF₃Ph,2b;R = 2,6-Me₂Ph,2c;R = 2,6-iPr₂Ph,2d;R = cyclohexyl,2e;Ar = C₆H₂tBu₂（2,4）,R = 2,6-iPr₂Ph,x = 0,2f） have been evaluated as the active catalysts for ethylene/1-hexene copolymerization in the presence of Et₂AlCl.The ligand substitution pattern and the catalyst structure model significantly influenced the polymerization behaviors such as the catalytic activity,the molecular weight and molecular weight distribution of the copolymers etc.The highest catalytic activity of 8.82 kg PE/（mmol_V·h） was observed for vanadium catalyst 2d with two 2,6-diisopropylphenyl substituted salicylaldiminato ligands.The copolymer with the highest molecular weight was obtained by using mono salicylaldiminato vanadium catalyst 1f having ligands with tert-butyl at the ortho and para of the aryloxy moiety.     

Coordination polymers and discrete complexes of Ag(I)-N-(pyridylmethylene)anilines: synthesis,crystal structures and photophysical properties

Reactions of AgO₂C₂F₃ with (E)-N-(pyridylmethylene)aniline in which the pyridyl N is in the p- or m-position yielded two 1-D coordination polymers, [(AgO₂C₂F₃)₂(L_a)₂]_n (L_a = (E)-2,6-diisopropyl-N-(pyrid-3-ylmethylene)aniline) (1) and [(AgOC₂F₃)₂(L_d)₂]_n (L_d = (E)-2,6-diisopropyl-N-(pyrid-4-ylmethylene)aniline) (5), and three discrete complexes, [(AgO₂C₂F₃)₂(L_a)₄] (2), [AgO₂C₂F₃(L_b)₂] (L_b = (E)-N-(pyrid-4-ylmethylene)aniline) (3) and [(AgOC₂F₃)₂(L_c)₄] (L_c = (E)-2,6-dimethyl-N-(pyrid-4-ylmethylene)aniline) (4). The structures were determined by MS, FT-IR and NMR spectroscopies, elemental analysis and single crystal XRD. 1 is an organometallic coordination polymer with silver in η¹-arene coordination, but is a discrete dimeric complex 2 when crystallized from warm diethylether. The geometries around silver(I) in 1 and 4 are tetrahedral, ‘inverted seesaw’ in 2 and T-shaped in 3 and in all the anion seems to play a role. Ag(I) centers in 5 have distorted trigonal bipyramid and inverted seesaw geometries. The trifluoroacetate anions in these complexes display variable monodentate and short bridging coordination patterns. All complexes absorb and strongly emit UV-Vis radiation at room temperature.     

Synthesis,spectral and thermal properties of macrocyclic zinc(II) complexes

The new zinc ternary complexes [Zn(cyclen)NO₃]ClO4 (I), [Zn₂(cyclen)₂(m-nic)](ClO₄)₃ (II), [Zn₂(cyclen)₂(m-pic)](ClO₄)₃ (III) (cyclen=1,4,7,10-tetraazacyclododecane; nic=nicotinic acid; pic=picolinic acid) were synthesized and their spectral and thermal properties were investigated. The compounds were characterized by elemental analysis, IR spectroscopy and TG/DTG, DTA methods. Moreover, the way of coordination of pyridinecarboxylate anions was proposed on the basis of the spectral data and consequently proved with results of X-ray structure analysis. This revised version was published online in August 2006 with corrections to the Cover Date.     

Synthesis and structure of mononuclear copper(II) complexes with acyclic Schiff-base ligands containing organotellurium substituents: a comparative study with selenium analogs

Tellurium-bearing acyclic Schiff bases, 2,6-bis({N-[2-(phenyltellurato)ethyl]}benzimidoyl)-4-methylphenol (HL³ ) and 2,6-bis({N-[3-(phenyltellurato)propyl]}benzimidoyl)-4-methylphenol (HL⁴ ) of the Te₂N₂O type have been prepared by condensation of 4-methyl-2,6-dibenzoylphenol (mdbpH) with the appropriate phenyltellurato(alkyl)amine. HL³ and HL⁴ have been characterized by mass spectrometry, IR, electronic and ¹H-NMR spectroscopies and cyclic voltammetry. Their reactions with Cu(II) acetate monohydrate in a 2?:?1 molar ratio in methanol yield [(C₆H₂(O)(Me){(C₆H₅)C=N(CH₂)_nTe(C₆H₅)}{(C₆H₅)C=O})₂Cu] (3 (n?=?2), 4 (n?=?3)) as suggested by analytical and spectroscopic data and single crystal X-ray crystallography of 3. In both complexes, one arm of the ligand undergoes hydrolysis at the C=N position and two molecules of the partially hydrolyzed ligand coordinate to Cu(II) through imido nitrogen and the phenolic oxygen. The telluriums do not form part of the copper(II) distorted square planar coordination sphere which has a trans-CuN₂O₂ core. Electrochemical studies of 3 and 4 indicate quasi-reversible reductions (E°′?=??1.113?V (3) and ?1.149?V (4)) corresponding to the reduction of copper(II) to copper(I). The interactions of 3 and 4 with calf thymus DNA, investigated by spectrophotometry and cyclic voltammetry, indicate that 3 and 4 bind to DNA via intercalation, and the binding affinity of 3 is lower than that of its selenium analog.     

Iron(II) complexes containing the 2,6-bis-iminopyridyl moiety. Synthesis,characterization, reactivity,and DNA binding

Two iron(II) complexes, [Fe^II(py^tBuN₃)₂](FeCl₄) (1) and [Fe^II(py^tBuMe₂N₃)Cl₂] (2), with sterically constrained py^tBuN₃ and py^tBuMe₂N₃ chelate ligands (py^tBuN₃ = 2,6-bis-(aldiimino)pyridyl; py^tBuMe₂N₃ = 2,6-bis-(ketimino)pyridyl), have been synthesized and characterized by elemental analysis, IR, UV–vis spectra, and preliminary X-ray single-crystal diffraction. The latter revealed that Fe(II) in 1 is six-coordinate by six nitrogen donors from two bisiminopyridines in a distorted octahedron. Complex 2 reacts with thiourea with a second-order rate constant k₂ = (2.50 ± 0.05) × 10^?3 M^?1 s^?1 at 296 K, and the reaction seemed to be slow. In a similar way, the interaction of 2 and DNA was studied by fluorescence and absorption spectroscopy. The results revealed that 2 caused fluorescence quenching of DNA through a dynamic quenching procedure. The binding constants K_A, K_app, and K_SV as well as the number of binding sites between 2 and DNA were determined.     

Synthesen von Heterocyclen, 85. Mitt.: Über die α-Acyllactonumlagerung von 5-Benzoyl-dehydracetsäure

Zusammenfassung Die vonButt undElvidge aufgefundenen Isomeren, 4-Hydroxy-5-acetyl-6-phenyl-pyron-(2) (1) und 4-Hydroxy-5-ben-zoyl-6-methyl-pyron-(2) (2), ergeben bei der Umsetzung mit POCl₃ und Eisessig 5-Benzoyl-dehydracetsäure (3). Im Gegensatz zur Dehydracetsäure² reagiert 5-Benzoyl-dehydracetsäure (3) in alkohol. HCl zum 2,6-Dimethyl-3-äthoxycarbonyl-5-benzoyl-pyron-(4) (6). Die Struktur dieser Verbindung wird auf chemischem und physikalischem Wege abgeleitet.Mit wäßr. HCl läßt sich3 in 2,6-Dimethyl-5-benzoyl-pyron-(4) (5) umwandeln.

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The isomeric compounds¹ 4-hydroxy-5-acetyl-6-phenyl-pyron-2 (1) and 4-hydroxy-5-benzoyl-6-methyl-pyron-2 (2) yield 5-benzoyl-dehydroacetic acid (3) if with glacial acetic acid and POCl₃. In contrast to dehydroacetic acid² 5-benzoyl-dehydroacetic acid (3) reacts in ethanolic HCl to 2,6-dimethyl-3-carbethoxy-5-benzoyl-pyron-(4) (6).However, with aquenous HCl3 is converted to 2.6-dimethyl-5-benzoyl-pyron-(4) (5).

     

Synthesis,structure, and catalytic bromination of supramolecular oxovanadium complexes containing oxalate

Three supramolecular complexes, [VO(phen)(C₂O₄)(H₂O)]·CH₃OH (1) [(VO)₂(u₂-C₂O₄)(C₂O₄)₂(H₂O)₂]·L·H₂O (2), and [(4,4′-bipyH₂)_0.5]⁺[VO₂(2,6-dipic)]^?·2H₂O (3) (phen?=?1,10-phenanthroline 4,4′-bipy?=?4,4′-bipyridine, 2,6-dipic?=?2,6-pyridinedicarboxylic, L?=?1,4-bis((3,5-dimethyl-1H-pyrazol-1-yl)methyl)benzene), have been prepared and characterized by elemental analysis, IR, and UV–vis spectroscopy and single-crystal diffraction analysis. Structural analysis shows that the three complexes all contain carboxylate and V=O moiety; vanadium of 1 and 2 are six coordinate with distorted octahedral geometry with N₂O₄ and O₆ donor sets, respectively, while 3 is five coordinate with distorted trigonal bipyramidal geometry with a NO₄ donor set. The complexes exhibit catalytic bromination activity in the single-pot reaction for the conversion of phenol red to bromophenol blue in H₂O–DMF at 30?±?0.5?C with pH 5.8, indicating that they can be considered as functional model vanadium-dependent haloperoxidases. In addition, electrochemical behaviors are also studied.     

Bis(oxamato)palladate(II) complexes: synthesis,crystal structure and application to catalytic Suzuki reaction

New bis(oxamato)palladate(II) complexes, [Pd(H₂O)₄][Pd(2,6-Me₂pma)₂]·2H₂O (1), (n-Bu₄N)₂[Pd(2,6-Me₂pma)₂]·2H₂O (2a), and (n-Bu₄N)₂[Pd(2,6-Me₂pma)₂]·2CHCl₃ (2b) (2,6-Me₂pma = N-2,6-dimethylphenyoxamate and n-Bu₄N⁺ = tetra-n-butylammonium), have been synthesized and the structures of 1 and 2b characterized by single-crystal X-ray diffraction. Complex 1 is a double salt constituted by tetraaquapalladium(II) cations and bis(oxamato)palladate(II) anions interlinked by hydrogen bonds. The palladium(II) ions in 1 are four-coordinate with two oxygens and two nitrogens from two fully deprotonated oxamate ligands (anion), and four water molecules (cation) building centrosymmetric square-planar surroundings. Centrosymmetric bis(oxamato)palladate(II) anions occur in 2b as in 1, the charge balance in this compound being ensured by the bulky n-Bu₄N⁺. The catalytic role of 1 and 2a for the Suzuki reaction has been investigated by using a series of aryl iodide/bromide derivatives in the conventional organic medium dimethylformamide. The tetraaquapalladium(II) unit in 1 appears to be active in the catalytic Suzuki cross-coupling reactions, but it readily decomposes to inactive palladium black.     

Thermal behaviour of new Ni(II) and Cu(II) complexes with macrocyclic ligands functionalised with 1,2,4-triazole

The investigations concerning the thermal behaviour of a series of Ni(II) and Cu(II) complexes of type [NiLCl₂]·mH₂O ((1) L:L₁, m=6; (3) L:L₂, m=4) or [CuLCl]_nCl _n ·mnH₂O ((2) L:L₁, m=6; (4) L:L₂, m=4) are presented. The ligands L(1) and L(2) have been synthesised by template condensation of 3,6-diazaoctane-1,8-diamine or 1,2-diaminoethane with formaldehyde and 2-amino-4H-1,2,4-triazole. The bonding and stereochemistry of the complexes have been characterised by IR, electronic and magnetic studies at room temperature. The in vitro qualitative and quantitative antimicrobial activity assays showed that the complexes exhibited variable antimicrobial activity against planktonic as well as biofilm embedded Gram-negative, Gram-positive and fungal strains. The thermal behaviour provided confirmation of the complexes composition as well as the number and nature of water molecules and the intervals of thermal stability.     

Seven-coordinate iron(II) complexes of sulfur-based N3S2-macrocyclic ligands: synthesis,properties, and crystal structure

The reaction of pyridine-2,6-dicarbaldehyde or 2,6-diacetylpyridine with 1,2-bis(o-aminophenylthio)ethane (1) in acetonitrile in the presence of stoichiometric amounts of iron(II) perchlorate gave the complexes [(pyN₃S₂)Fe^II(ClO₄)₂] (4) and [(pyN₃Me₂S₂)Fe^II(ClO₄)₂] (5) of the 15-membered N₃S₂ macrocyclic ligands, pyN₃S₂ ?=?{6,7-dihydro-15,19-nitrilobenzo(e,p)(1,4,7,15)dithiadiazacyclo-heptadecine-N,N′,N″,S,S′} and pyN₃Me₂S₂?=?{6,7-dihydro-16,18-dimethyl-15,19-nitrilobenzo(e,p)(1,4,7,15)dithiadiazacyclo-heptadecine-N,N′,N″,S,S′}, respectively. Physical measurements led to the conclusion that these complexes contained seven-coordinate iron(II) and a single-crystal X-ray examination of 4 confirmed this. Coordination of the Fe(II) center in 4 is best described as distorted pentagonal-bipyramidal with the three nitrogen atoms and two sulfur donors of the macrocycle defining the pentagonal plane and the perchlorate ions occupying axial positions. Room temperature (293?K) magnetic moments of 4 and 5 (μ _eff?=?4.9 and 4.7 B.M., respectively) are close to the value predicted for high-spin d⁶ systems.     

In situ synthesis,crystal structures,and luminescence of two new tetrazole complexes

The synthesis, crystal structures, and luminescent properties of two new complexes containing tetrazolyl ligands are described. Refluxing a mixture of fipronil (fipronil = (±)-5-amino-1-[2,6-dichloro-4-(trifluoromethyl)phenyl]-4-[(trifluoromethyl)sulfinyl]-1H-pyrazole-3-carbonitrile), sodium azide, and CuCl₂ in ethanol and water gives complex 1, [M(L)₂](H₂O)₂] ? 2H₂O (HL = (±)-5-amino-1-[2,6-dichloro-4-(trifluoromethyl)phenyl]-4-[(trifluoromethyl)sulfinyl]-1H-pyrazole-3-tetrazole, M = Cu). Hydrothermal reaction of fipronil, sodium azide, and Cd(ClO₄)₂ in the presence of water and ethanol (Demko–Sharpless tetrazole synthesis) yields 2, [M(L)₂](H₂O)₂] ? 2H₂O (M = Cd). The metals in both complexes are six coordinate from two water molecules, two nitrogens from different tetrazolyl groups, and two nitrogens from pyrazolyl groups. Photoluminescence studies reveal that 2 exhibits strong blue fluorescent emission at λ _max = 451 nm in solid state at room temperature.