Synthesis and properties of azole-substituted ferrocenes

4-Ferrocenyltriazole, 4-(4-ferrocenylphenyl)triazole, 4-ferrocenyltetrazole, and 4-(4-ferrocenylphenyl)tetrazole have been prepared. Redox potentials and decomposition temperatures were evaluated and all the compounds were crystallographically characterized; in most cases, weak intermolecular CH?N hydrogen bonds (H?N dist. = 2.3-2.5 Å) were formed between the azole moieties. Two polymorphs were found for 4-ferrocenyltetrazole, formed with either CH?N or π-π interactions.     

Synthesis and characterisation of new copper(II) coordination polymers constructed from pyrazine–tetrazole ligands with the formation of a water cluster

Three novel bis-tetrazole ligands (1–3) containing carboxylate functional groups on the tetrazole rings and a rigid pyrazine linker unit, for the construction of coordination polymers when coordinated to copper(II) ions, were synthesised and structurally characterised. The use of pyrazine as a rigid linker between the two tetrazole units was expected to increase the dimensionality of the solid phase polymeric network of the resulting copper(II)-containing compounds. X-ray structures of the ligands revealed the effect of the substitution position on the tetrazole ring of the ester/carboxylate groups. Higher solid phase dimensionality was successfully achieved as shown by the layered two-dimensional (2-D) coordination structure being formed when the pyrazine bis-tetrazole systems were reacted with copper(II) chloride, although not in the expected manner. There was no interaction between the pyrazine nitrogen atoms and the metal ion. Computational studies showed that this was probably due to the geometry, required by the copper ion, to be involved in the close packing between the layers. The 2-D coordination polymer based on the asymmetric substituted pyrazine bis-tetrazole, [Cu(4)(H₂O)](H₂O)₂, was further connected into a three-dimensional (3-D) coordination network through hydrogen bonding between H₂O molecules. These H₂O molecules were connected as a unique 1-D chain throughout the structure.     

Synthesis and properties of potassium 5,5'-azobis (1-nitraminotetrazolate): A green primary explosive with superior initiation power

Potassium 5,5'-azobis(1-nitraminotetrazolate), (K₂ABNAT), a new green primary explosive, was synthesized via a safe and convenient synthetic procedure based on methylcarbazate and cyanogen azide. The compound was characterized by single-crystal X-ray diffraction, IR spectroscopy, Raman spectroscopy, multinuclear NMR spectroscopy, elemental analysis, and differential scanning calorimetry (DSC). With the calculated (CBS-4M) heat of formation (617.0 kJ/mol) and the room temperature X-ray density (2.11 g/cm³), impressive values for the detonation parameters such as detonation velocity (8367 m/s) and pressure (31.5 GPa) were computed using the EXPLO5 program. The superior calculated energetic performance show it could serve as a green replacement for the widely used primary explosive, lead(II) azide, which contains toxic ingredient.     

Synthesis of some new 4-oxo-thiazolidines,tetrazole and triazole derived from 2-SH-benzothiazole and antimicrobial screening of some synthesized

A new heterocyclic derivative of 2-mercaptobenzothiazole (MBT) comprising 4-oxothiazolidines, tetrazole and triazole, through the reaction of (MBT) with hydrazine hydrate obtained 2-hydrazobenothiazol (1), which was condensed with various aromatic aldehydes. Azomethine derivatives (2a–c) are converted into a number of 4-oxothiazolidines (3a–c) and tetrazole derivatives (4a–c), through the reaction of azomethine derivatives (2a–c) with mercaptoacetic acid and sodium azide, respectively. Also the reaction of compound (1) with triethylorthoformate and nitrous acid to produce the corresponding (triazole and tetrazole) benzothiazole (5,6) was reported.Triazole moieties reported condensation (MBT) with ethylbromo acetate and potassium hydroxide by the fusion method and resulted in ester-2-mercaptobenzothiazole (7), which was treated with hydrazine hydrate to give a hydrazine derivative (8), then converting these compounds (8) to phenyl semicarbazide (9) and phenyl thiosemicarbazide (10) derivatives. Cyclization compounds (9,10) in alkaline media (4 N·NaOH) gave triazoles compounds (11,12). Furthermore the compound (8) was converted to the dithiocarbazate salt (13) which was then cyclized with hydrazine hydrate to give substituted triazole (14). The prepared compounds were identified by spectral methods (FTIR, ¹H NMR, ¹³C NMR) and some of its physical properties were measured and furthermore the effects of the preparing compounds on some strains of bacteria were studied.     

Spin Transition of 1D, 2D and 3D Iron(II) Complex Polymers The Tug-of-War between Elastic Interaction and a Shock-Absorber Effect

Summary.  The structures of linear chain Fe(II) spin-crossover compounds of α,β- and α,ω-bis (tetrazol-1-yl)alkane type ligands are described in relation to their magnetic properties. The first threefold interlocked 3-D catenane Fe(II) spin-transition system, [μ-tris(1,4-bis(tetrazol-1-yl)butane-N1,N1′) iron(II)] bis(perchlorate), will be discussed. An analysis is made among the structures and the cooperativity of the spin-crossover behaviour of polynuclear Fe(II) spin-transition materials. Corresponding author. E-mail: koning@iacgu7.chemie.uni-mainz.de Received April 8, 2002; accepted April 18, 2002     

5-(1-芳基-1-吡咯-2-基)-1氢-四唑类化合物的合成与表征

利用阳极氧化反应, 将一系列N-芳基吡咯电氰化, 区域专一地得到吡咯氰化物2, 分离收率为76%~85%. 将其与叠氮化钠反应, 合成了一系列具有潜在血管紧张素Ⅱ受体(AT)拮抗活性的新型四唑化合物. 该合成路线的原料易得, 并以阳极氰化芳香氮杂环引入氰基为关键步骤, 可作为在芳香氮杂环上引入四唑基团的通用合成路线.     

Synthesis, structure and fluorescence of novel cadmium(II) and silver(I) complexes with in situ ligand formation of 1-(5-tetrazolyl)-4-(imidazol-1-ylmethyl)benzene

Hydrothermal reactions of cadmium(II) or silver(I) salt, NaN₃, 4-(imidazol-1-ylmethyl)benzonitrile (IBN) yield three coordination complexes, [Cd(L)₂(H₂O)₂]·3H₂O (1), [Cd₃(L)₅(OH)] (2) and [Ag₂(L)₂] (3) where HL=1-(5-tetrazolyl)-4-(imidazol-1-ylmethyl)benzene. The crystal structure analysis revealed that 1 has 1D hinged-chain structure containing 24-membered ring with a Cd···Cd intra-chain distance of 13.18 Å, while 2 is 1D ladder-like chain with Cd₃O core. However, the complex 3 is a 3D 4-connected framework with Schläfli symbol of (4²·6³·8)(4³·6²·8). The L⁻ ligand was found to show four different coordination modes in 1-3, as 2-, 3- and 4-connector, respectively. The results indicate that the coordination modes of the ligand and metal centers with different coordination geometry have great influence on the structures of the complexes. In addition, the photoluminescence of the complexes were studied in the solid state at room temperature.     

Urea mediated 5-substituted-1H-tetrazole via [3 + 2] cycloaddition of nitriles and sodium azide

A simple, new and convenient metal free procedure for the synthesis of 5-substituted 1H-tetrazoles using various nitriles and sodium azide in the presence of urea and acetic acid with good to high yields is developed. The reaction plausibly proceeds through in situ formation of urea azide active complex without toxic and/or expensive metal catalysts.     

New convenient synthesis of 2,3-diaminothieno[2,3-d]pyrimidin-4(3H)-one derivates from substituted alkyl 2-(1H-tetrazol-1-yl)thiophene-3-carboxylates

4,5-Disubstituted and 4-substituted alkyl 2-amino-thiophene-3-carboxylates react with triethyl orthoformate and sodium azide in acetic acid to yield new 2-(1H-tetrazol-1-yl)-4-R¹-5-R²-thiophene derivates. It was established that the reaction of these tetrazoles with hydrazine generates the insufficiently studied 2,3-diaminothieno[2,3-d]pyrimidin-4(3H)-one system. It is significant that the reaction mentioned above is the unique tetrazole ring cleavage under the action of hydrazine.