Metal Perchlorate Complexes Research Articles

1‐Amino‐5‐methyltetrazole in Energetic 3 d Transition Metal Complexes – Ligand Design for Future Primary Explosives

AbstractNew lead‐free primary explosives are needed for safe future ignition and initiation applications. Especially, ignition by low‐energy laser irradiation has been demonstrated to be a valuable method. For this technology, primary explosives with safer sensitivities are needed. In order to adjust the desired properties of the neat primary explosives, we follow the concept of “energetic coordination compounds” (ECC) in which the ligand significantly alters the final properties. As the result of a study where 1‐amino‐5H‐tetrazole (1‐AT) was used as one of the most endothermic ligands, yielding materials with outstanding performance but very high sensitivities, in this work its 5‐methyl analogue 1‐amino‐5‐methyltetrazole (1‐AMT, 1) was synthesized and applied as ligand. For a short evaluation, metal perchlorate complexes [M(1‐AMT)6](ClO4)2 of manganese(II), iron(II), and zinc(II) as well as [Cu(1‐AMT)4(H2O)](ClO4)2 were prepared. All compounds were intensively characterized e. g., by XRD, IR, EA, TGA, DTA as well as sensitivity measurements (impact, friction, BDIS, and ESD). The obtained materials show reduced performance but they are safer to handle than the corresponding 1‐AT derivatives. Moreover, the satisfactory performances of ECC 3 and 4 were impressively demonstrated by PETN initiation and laser ignition experiments.

Kinetics of thermolysis of some transition metal perchlorate complexes with 1,6-diaminohexane ligand

Abstract Three transition metal perchlorate complexes of general formula [M(dah)2)](ClO4)2 (where M = Zn, Cu, and Ni; dah = 1,6-diaminohexane) have been prepared, and characterized by elemental analysis, infrared spectroscopy (IR), and gravimetric method. The thermal decomposition has been studied by thermogravimetry (TG), differential thermal analysis (DTA), and differential scanning calorimetry (DSC). Kinetics parameters of their thermolysis were evaluated by model-fitting and isoconversional methods using isothermal TG data. Model-fitting method has given the single value of activation energy (E) whereas; isoconversional method yields a series of E values which vary with the extent of conversion. Further ignition delay of these complexes was measured to see the response toward rapid heating with varying amounts. The thermal stability of the complexes decreases in the order as: [Zn(dah)2)](ClO4)2 > [Cu(dah)2)](ClO4)2 > [Ni(dah)2)](ClO4)2

Preparation, X-ray crystallography and thermal decomposition of transition metal perchlorate complexes with perchlorate and 2,2′-bipyridyl ligands

Three transition metal perchlorate complexes of 2,2′-bipyridyl such as [Mn(bipy) 2(H 2O)(ClO 4)]ClO 4, [Cu(bipy)(ClO 4) 2(H 2O) 2], [Zn(bipy) 2(H 2O)](ClO 4) 2 have been prepared, and characterized by X-ray crystallography. Their thermal decomposition has been studied using iso and non-isothermal thermogravimetry (TG); differential scanning calorimetry (DSC). Kinetics parameters were evaluated by model-fitting and isoconversional methods. Their thermolytic pathways have also been suggested which involves decomposition followed by explosion. The Mn and Cu complexes decompose in single step whereas Zn complex decomposes in two steps. The coordination number of Mn and Cu atoms is found to be six and that of Zn is five. In order to evaluate the response of rapid heating, explosion delay ( D E ) measurements were undertaken. The explosion delay and activation energy were found to decrease in the order: Zn > Cu > Mn.

Preparation, X-ray Crystallography, and Thermal Decomposition of Some Transition Metal Perchlorate Complexes of Hexamethylenetetramine

The perchlorate complexes of manganese, nickel, and zinc with hexamethylenetetramine (HMTA) of the general formula [M(H2O-HMTA-H2O)2(H2O-ClO4)2(H2O)2] (where M=Mn, Ni, and Zn) have been prepared and characterized by X-ray crystallography. Thermal studies were undertaken using thermogravimetry (TG), differential thermal analysis (DTA), and explosion delay (DE) measurements. The kinetics of thermal decomposition of these complexes was investigated using isothermal TG data by applying isoconversional method. The decomposition pathways of the complexes have also been proposed. These were found to explode when subjected to higher temperatures.

New supramolecular complexes generated from Mn II, Fe II, Co II, Zn II, Fe III with a bent dipyridyl ligand: Metal- and anion-directed assembly

Assemblies of an angular dipyridyl ligand 2,5-bis(4-pyridyl)-1,3,4-oxadiazole (4-bpo) with a series of metal perchlorate afford five new supramolecular complexes with the general formula of [M(4-bpo) 2(H 2O) 4] · (4-bpo) 2 · (anion) · (solvent), in which M = Mn II for 1, Fe II for 2, Co II for 3, Zn II for 4, and Fe III for 5. Although similar molecular structures and compositions are found for these mononuclear complexes, they display two types of supramolecular lattices. Complexes 1, 4 and 5 similarly crystallize in space group P2/ n or P2/ c. The complex cations, free 4-bpo and lattice water are linked to generate 2D layered frameworks with the aid of hydrogen bonding, and the counter anions are located within and between (also methanol in 5) these 2D arrays. However, complexes 2 and 3 are isostructural in space group P 1 ¯ . Two types of alternate 2D layers consisting of complex cations and free 4-bpo components, respectively, are observed with the anions and lattice water locating between them. These motifs are interlinked by complicated hydrogen-bonding to form a 3D intercalated network. Moreover, when Co(NO 3) 2 is used instead of Co(ClO 4) 2 in the assembly of 3, a 1D polymeric chain complex {[Co(4-bpo)(H 2O) 2(NO 3) 2](H 2O) 3} n ( 6) is generated. These results indicate that the choice of metal ion and anion exerts a significant influence on governing the target complexes. A comparison of the structural features for all metal perchlorate complexes with 4-bpo is also briefly discussed.

Studies on energetic compounds

Bis(propylenediamine)metal perchlorate (BPMP) complexes like [M(pn)2](ClO4)2 (where M=Cr, Mn, Ni, Cu, Zn and pn=propylenediamine) have been prepared and characterized by gravimetric methods, infrared and elemental analysis. Thermal properties have been studied using simultaneous thermogravimetry-differential thermal analysis in atmospheres of nitrogen and air to examine the effect of atmospheric change on thermal decomposition of these complexes. Changing of the atmosphere does not cause any measurable changes in the decomposition of complexes. However, as indicated by thermoanalytical techniques, the thermal stability of present complexes decreases in the order: [Cr(pn)2](ClO4)2>[Mn(pn)2](ClO4)2>[Zn(pn)2](ClO4)2>[Ni(pn)2](ClO4)2>[Cu(pn)2](ClO4)2. Isothermal thermogravimetry, over the temperature range of decomposition has been done for all the complexes. An analysis of the kinetics of thermal decomposition was made using a model fitting procedure as well as an isoconversional method, independent of any model. The results of both kinetic approaches have been discussed critically. The explosion delay (DE) was measured to investigate the trend of rapid thermal analysis.

Kinetics of thermolysis of some transition metal perchlorate complexes with 1,4-diaminobutane ligand

Three metal perchlorate complexes of general formula [M(dab) 2](ClO 4) 2·xH 2O (where M = Zn, Cu and Ni; dab = 1,4-diaminobutane) have been prepared and characterized by gravimetry, infrared spectroscopy (IR) and elemental analysis. Thermolysis has been studied by thermogravimetry (TG) in air and simultaneous thermogravimetry–differential thermogravimetry–differential thermal analysis (TG–DTG–DTA) and differential scanning calorimetry (DSC) in N 2 atmosphere. Isothermal gravimetry over the temperature range of initial decomposition of the complexes has been done to evaluate the kinetics. Both model fitting and isoconversional methods have been used for the evaluation of the kinetics. Model fitting gives a single value of activation energy ( E) whereas the isoconversional method yields a series of E values which vary with extent of conversion. Ignition with varying amounts of the complexes was measured to see the response to rapid heating. The thermal stability order of the complexes is [Zn(dab) 2](ClO 4) 2 ≫ [Cu(dab) 2](ClO 4) 2.2H 2O ≈ [Ni(dab) 2](ClO 4) 2.

Studies on energetic compounds part 37: kinetics of thermal decomposition of perchlorate complexes of some transition metals with ethylenediamine

Five bis(ethylenediamine)metal perchlorate (BEMP) complexes like [M(en) 2](ClO 4) 2 (where M=Mn, Co, Ni, Cu, Zn and en=ethylenediamine) have been prepared and characterized by gravimetric methods, infrared spectroscopy (IR) and elemental analysis. Thermal decomposition studies have been undertaken using simultaneous thermogravimetry (TG) and differential thermal analysis (DTA) in nitrogen atmosphere. Non-isothermal TG and DTA studies have also been carried out separately in air to examine the effect of atmosphere on thermolysis of these complexes. Thermal stability of the complexes was found to decrease in the order: [Zn(en) 2](ClO 4) 2>[Mn(en) 2](ClO 4) 2>[Ni(en) 2](ClO 4) 2>[Cu(en) 2](ClO 4) 2>[Co(en) 2](ClO 4) 2. Isothermal TG over the temperature range of decomposition of all these complexes, has been done to evaluate the kinetics of decomposition. Both model fitting and model free isoconversional methods have been used to analyse the kinetics. Isoconversional method has been found to be superior over the conventional model fitting method and is able to describe the complex decomposition of these complexes. It indicates that the values of activation energy vary with the extent of conversion ( α) while model fitting method results in a single value of E for overall decomposition process which cannot be attributed to any process under such a complex decomposition reaction. Explosion delay ( D E) measurement has been carried out to investigate the response of these complexes under the condition of rapid heating.

Studies on energetic compounds part 37: kinetics of thermal decomposition of perchlorate complexes of some transition metals with ethylenediamine

Five bis(ethylenediamine)metal perchlorate (BEMP) complexes like [M(en)2](ClO4)2 (where M=Mn, Co, Ni, Cu, Zn and en=ethylenediamine) have been prepared and characterized by gravimetric methods, infrared spectroscopy (IR) and elemental analysis. Thermal decomposition studies have been undertaken using simultaneous thermogravimetry (TG) and differential thermal analysis (DTA) in nitrogen atmosphere. Non-isothermal TG and DTA studies have also been carried out separately in air to examine the effect of atmosphere on thermolysis of these complexes. Thermal stability of the complexes was found to decrease in the order: [Zn(en)2](ClO4)2>[Mn(en)2](ClO4)2>[Ni(en)2](ClO4)2>[Cu(en)2](ClO4)2>[Co(en)2](ClO4)2. Isothermal TG over the temperature range of decomposition of all these complexes, has been done to evaluate the kinetics of decomposition. Both model fitting and model free isoconversional methods have been used to analyse the kinetics. Isoconversional method has been found to be superior over the conventional model fitting method and is able to describe the complex decomposition of these complexes. It indicates that the values of activation energy vary with the extent of conversion (α) while model fitting method results in a single value of E for overall decomposition process which cannot be attributed to any process under such a complex decomposition reaction. Explosion delay (DE) measurement has been carried out to investigate the response of these complexes under the condition of rapid heating.

Synthesis and structural studies on three-dimensionally hydrogen-bonded metal perchlorate complexes with 1,3-dimethyllumazine and 1,3,6,7-tetramethyllumazine. Crystal structure of diaqua-bis(1,3,6,7-tetramethyl-pteridine2,4(1 H,3 H)-dione-O 4,N 5) copper(II) perchlorate dihydrate

In aqueous solution, M II(ClO 4) 2 (Mn  Mn, Co, Ni, Cu, Zn, Cd and Hg) reacted with 1.3-dimethyllumazine 9DLM) and 1,3,6,7-tetramethyllumazine (DLMD) (lumazine = (1 H,3 H)-pteridin-2,4-dione) to give complexes with general formula Mp II(ClO 4) 2(LM) 2 · nH 2O. These compounds have been characterized by means of the analytical techniques (elemental analysis and thermogravimetry), spectral methods (IR, 13C and 1H NMR, UV-VIS-NIR, electron paramagnetic resonance) and magnetic measurements (77–290 K). Single-crystal X-ray diffraction studies have been made on the complex [Cu(DLMD) 2(H 2O) 2](ClO 4) 2·2H 2O. This compound crystallizes in the monoclinic system. P2 1/ c space group, Z = 2, with a = 8.764(1), b = 13.7932(8), c = 14.792(1) A ̊ , β = 116.02(1)°, V = 1602.9(3) A ̊ 3 , and R = 0.0728 for 4648 independent reflections and 224 parameters. The metal ion occupies an center and exhibits a distorted octahedral coordination. The coordination octahedron is flattened, the equatorial plane consisting of two N(5) and two O(4) atoms of pteridine ligands: the two axial sites are occupied by two oxygen atoms from the coordinated water molecules. The monomeric units together with non-coordinated water molecules and perchlorate anions are involved in a complex three-dimensional H-bonds network, the pteridine moieties being packed following planes roughly parallel to b axis, and perpendicular to the [5 4 21] direction. These planes are separated by a mean distance of 7.3 Å.

Infrared, thermal and structural properties of first transition series metal chloride and perchlorate complexes of quinoxaline

The chloride complexes of divalent Mn, Fe, Co, Ni, Cu and Zn containing one or two quinoxaline molecules and different numbers of H 2O molecules, when subjected to thermal analysis under dynamic N 2 atmosphere, decomposed to the metal chloride which then gave the metal oxide. The chlorides of Cu and Zn partly sublimed. The perchlorate complexes contained two or three quinoxaline molecules and in the case of Mn, Fe and Zn did not decompose to pure metal perchlorate during the heating before an explosion occurred; this depended on the heating rate. The IR spectra of the complexes show M-N bands under 500 cm −1, confirming the quinoxaline coordination. Copper in particular shows a tendency to form polymeric structures. The correlation between the results and the complex structure is discussed.

ChemInform Abstract: Facilitation of the Syntheses of Metal Perchlorate Complexes with Purines from Non‐aqueous Suspensions by Substituting Ethyl Acetate for Ethanol in the Interaction Medium.

AbstractUntersuchungen zeigen, daß die in siedendem Ethylacetat/Triethylorthoformiat durchgeführte lz2‐molare Umsetzung von hydratisierten 3d‐ Metallperchloraten [M:Cr(III), Mn(II), Fe(II), Fe(III), Co(II), Ni(II), Zn(II)] mit Purin‐Verbindungen meist zu isolierbaren lz2‐Addukten in bisher nicht erzielten, guten Ausb. führt.

Bis[bis{(diphenylphosphinyl)methyl}ethyl phosphinate](ethanol) copper(II) perchlorate: synthesis, crystal and molecular structure

Bis[bis{(diphenylphosphinyl)methyl}ethyl phoshinate]bis(ethanol) metal(II) perchlorate complexes, where metal = Co, Ni or Cu, have been prepared by the reaction of metal perchlorates and bis[(diphenylphosphinyl)methyl]ethyl phosphinate, (RPOEt), in absolute ethanol. The crystal structure of the copper complex is triclinic, space group P 1 , a = 13.688(7) Å, b = 14.424(10) Å, c = 9.865(2) Å, α = 110.43(4)°, β = 90.13(2)°, γ = 115.54(4)°, V = 1619.8 Å 3, Z = 1 and refined to R = 0.048 ( R w = 0.057). The structure consists of complex cations surrounded by perchlorate anions. Two RPOEt ligands and two ethanols are coordinated to the copper atom situated at the centre of symmetry 0, 0, 0. The RPOEt ligand is bidentate [CuO distances 1.969(4) Å, 2.312(4) Å], but the third oxygen atom from phosphoryl bonds is hydrogen bonded [2.669(6) Å], to the oxygen atom of ethanol molecule coordinated to the copper at 1.988(4) Å. The conformations of the ligand and chelate rings, magnetic data, molar conductance values, infrared and electronic spectra are given.

Facilitation of the syntheses of metal perchlorate complexes with purines from non-aqueous suspensions by substituting ethyl acetate for ethanol in the interaction medium

Facilitation of the syntheses of metal perchlorate complexes with purines from non-aqueous suspensions by substituting ethyl acetate for ethanol in the interaction medium

Metal complexes with 2-aminopyridine N-oxide, including N-oxide-bridged complexes of cobalt(II), nickel(II) and copper(II). Further studies on related pyridine N-oxide complexes

Metal complexes of 2-aminopyridine N-oxide (Hapo) have been characterised by infrared spectra, X-ray powder diffraction spectra, and by magnetic measurements and electronic spectra to liquid nitrogen temperature. Neutral Hapo appears to be an O-donor ligand in almost every case, according to spectroscopic evidence. The [M(Hapo) 6]X 2] complexes (M = Mn, Co and Ni; X drawn from ClO 4, BF 4 and NO 3) are octahedrally coordinated and [Cu(Hapo) 4](BFA 4) 2 is square planar. The complexes Co(Hapo) 2Br 2·C 2H 5OH, Ni(Hapo) 2Br 2, Cu(Hapo) 2(NO 3) 2, and the copper(II) halide complexes, are all antiferromagnetic and N-oxide bridged. Such bridging pyridine N-oxide, whilst common with copper(II), is rare with cobalt(II) and nickel(II). The temperature dependence of the magnetism of Ni(Hapo) 2Br 2 has been compared to that for various models. Other Hapo complexes with cobalt(II) and nickel(II) halides appear to be halide-bridged. Some previously reported complexes with pyridine N-oxide (po), of the type M(po)Hal 2·H 2O (M = Co, Ni), have been more fully characterised and are halide-bridged. The complexes [Fe(Hapo) 4Cl 2]Cl and [(Cr(Hapo) 4Cl 2]Cl·H 2O have trans-MO 4Cl 2 coordination. The complex Cu(apo) 2 contains deprotonated O,N-bonded ligand. The complexes Cu(apo) 2, [Cu(Hapo) 4](BF 4) 2, Cu(Hapo) 2(NO 3) 2 and the metal perchlorate complexes have been previously reported, the remaining complexes are new.

Synthesis and Characterisation of Metal Hydrazine Nitrate, Azide and Perchlorate Complexes

Abstract Metal hydrazine nitrate complexes of the type M(N2H4)Nn (NO3)2 where M = Mg, n = 2; M = Mn, Fe, Co, Ni, Zn and Cd and n = 3; metal dihydrazine azide complexes of the type M(N2H4)2 (N3)2 where M = Mg, Co, Ni and Zn; and Mg(N2H4)2 (C1O4)2 have been prepared by dissolving the respective metal powders in the solution of corresponding ammonium salts (NO3, N3 and C1O4) in hydrazine hydrate. These hydrazine complexes were also prepared by the conventional method involving the addition of alcoholic hydrazine hydrate to the aqueous solution of metal salts. The hydrazine complexes have been characterised by chemical analysis, infrared spectra and differential thermal analysis (DTA). Impact sensitivities of hydrazine complexes were determined by the drop weight method. The reactivity of these hydrazine complexes does not change with the method of preparation.

Peaceful pyrolysis—a novel method for the decomposition of metal-perchlorate complexes of organic ligands

Perchlorate complexes of vanadium(IV), iron(III), dysprosium, yttrium, copper(II) and nickel with the organic ligands dimethyl sulphoxide, antipyrine, 4-aminoantipyrine, 4-(2-hydroxynaphthyl)-azoantipyrine, and 4-(2,4-dihydroxyphenyl)azoantipyrine have been prepared and analysed for their metal content after decomposition by a non-explosive pyrolytic technique, viz. heating with ammonium chloride. The results obtained agree with those obtained by the standard methods. This pyrolytic technique is found to be very convenient, rapid and accurate.

ChemInform Abstract: HARD LIGANDS AS DONORS TO SOFT METALS. PART 3. CATIONIC BIS(SOLVENT) COMPLEXES OF PALLADIUM(II); CATIONS FOR CATALYSIS

AbstractBehandelt man den Dichlorokomplex (I) mit 2 Äquivalenten eines Silbersalzes in Gegenwart eines schwachen Lösungsmittelliganden, so bilden sich die kationischen Komplexe (II).

Transition metal tetrafluoroborate interactions with 2,6-lutidine N-oxide

The interactions of transition metal tetrafluoroborates with 2,6-lutidine N-oxide(L) in organic solvents were studied, under various conditions. A number of adducts of the types [CrL 6](BF 4) 3, [ML 4](BF 4) 2 (M = Fe, Cu, Zn, Cd), [CoL 4(FBF 3)](BF 4)·H 2O and [L 3NiL 2NiL 3](BF 4) 4 were isolated and characterized. In most cases, these compounds are similar to the corresponding metal perchlorate complexes (including the square-planar Fe 2+ complex, which is partially spin-paired (S = 1; μ eff = 3.55 μB)). The only differences are that the new Co 2+ complex involves coordinated FBF 3, while the 4:1 Co(ClO 4) 2 analog contains exclusively ionic ClO 4, and that, whereas the diamagnetic, square-planar [NiL 4] (ClO 4 2 complex remains unchanged for a long time before dimerizing to the paramagnetic [L 3NiL 2NiL 3](ClO 4) 4, with the [NiL 4](BF 4) 2 analog the monomeric species is unstable, dimerizing within a few hours. These differences were attributed to the significantly smaller steric hindrance exerted by BF 4 relative to ClO 4. In addition to the preceding adducts, a number of products of the types [L 3CoF 2CoL 3] (BF 4) 2, [(F 2BF 2)L(ROH)MF 2M(ROH)L(F 2BF 2)] (R = CH 3 for M = Mn; R = C 2H 5 for M = Ni) and MnLF(BF 4)·4MnF 2 were isolated. Formation of MF(BF 4) or MF 2 is accompanied by elimination of BF 3·L from the initially formed adducts. This reaction seems to be favored when the initial adducts of L with M(BF 4) 2 involves coordinated tetrafluoroborato ligands [1].

Hard ligands as donors to soft metals. Part 3. Cationic bis(solvent) complexes of palladium(II); cations for catalysis

Treatment of [Pd(dppe)Cl2], dppe = Ph2PCH2CH2PPh2, with 2 equivalents of a silver(I) salt in the presence of a solvent ligand (solvent) leads to the formation of [Pd(dppe)(solvent)2]Y2 where Y = ClO4 or BF4. In this way stable complexes with solvent = pyridine, O-bonded dimethyl sulphoxide, dimethylformamide, benzonitrile, o-toluonitrile, acetone, or water as well as (solvent)2= 1,6-dicyanohexane or o-phthalonitrile have been isolated and characterised. Complexes with solvent = methanol, ethanol, acetonitrile, or tetrahydrofuran are stable in solution; on attempted isolation the ethanol complex deposits palladium metal, the methanol and tetrahydrofuran perchlorate complexes yield the bis(perchlorato)-complexes [Pd(dppe)(OClO3)2], and the acetonitrile complex yields mainly [Pd(dppe)(NCMe)2][ClO4]2 with a small amount of perchlorate-co-ordinated complex. The co-ordinated perchlorate ligands are readily displaced in solution by any of the solvent ligands; the bis(acetone) complex is very sensitive to moisture yielding [Pd(dppe)(OH2)2][ClO4]2 on exposure to air. Attempts to displace acetone from [Pd(dppe)(OCMe2)2]2+ and perchlorate from [Pd(dppe)(OClO3)2] by carbon monoxide failed. The solvent molecules dichloromethane and benzene do not form palladium(II) complexes of the present type; treatment of [Pd(dppe)Cl2] with 2 equivalents of silver(I) perchlorate in dichloromethane–benzene yields [Pd(dppe)(OClO3)2]. Preliminary investigation of the catalytic abilities of these palladium(II) complexes has shown that [Pd(dppe)(OCMe2)2][ClO4]2 catalyses the hydrogenation of styrene to ethylbenzene at atmospheric pressure and 30 °C, which is remarkably high activity for palladium(II).