Dichloro[N,N‐dimethyl‐1‐(1‐methyl‐1H‐tetrazol‐5‐yl‐κN4)methanamine‐κN]copper(II)

The title compound, [CuCl₂(C₅H₁₁N₅)], is the first structurally characterized molecular chelate complex involving an α‐­amino­alkyl­tetrazole. There are two complex mol­ecules in the asymmetric unit. The ligand mol­ecules are bidentate. Both Cu atoms reveal rather distorted square‐planar coordinations. The complex mol­ecules are linked together by van der Waals interactions only.     

Endo- and exocyclic N-alkylation of 1- and 5-aminotetrazoles with t-BuOH-HClO4: synthesis of mono-, di-, and tri-tert-butyl substituted aminotetrazolium salts

A new method for the synthesis of 1,3,5-trisubstituted aminotetrazolium salts based on alkylation of 1- and 5-aminotetrazoles with the t-BuOH-HClO₄ system is presented. Depending on the structure of the tetrazole substrate and reaction conditions, alkylation proceeds at the endocyclic nitrogen atoms as well as at the 1- and 5-amino groups giving mono-, di-, and tri-tert-butyl substituted tetrazolium salts. An X-ray diffraction investigation of 3-tert-butyl-1,5-bis(tert-butylamino)tetrazolium perchlorate and 5-amino-1,3-di-tert-butyltetrazolium chloride was carried out.     

Copper(II), palladium(II) and platinum(II) chloride complexes with 5-amino-2-tert-butyltetrazole: Synthesis, characterization and cytotoxicity

Complexes CuL₃Cl₂, PdL₂Cl₂ and PtL₂Cl₂, where L is a novel ligand from the series of 2-substituted 5-aminotetrazoles, namely 5-amino-2-tert-butyltetrazole (1), have been synthesized by the reaction of metal(II) chlorides with 1 and characterized by IR spectroscopy, thermal and X-ray analyses. The crystallographic structural analysis of these complexes revealed that 1 acts as a monodentate ligand coordinated to the metal via endocyclic N4 atom. Platinum complex demonstrates promising cytotoxicity against human cervical carcinoma cells with IC₅₀ value average between those of cisplatin and carboplatin.     

4-Nitro-2-(1H-tetrazol-1-yl)­phenol

There are two symmetry-independent mol­ecules in the unit cell of the title compound, C₇H₅N₅O₃. The tetrazole and phenyl rings are essentially planar and are not coplanar in either mol­ecule [dihedral angles 30.2 (1) and 7.0 (1)°]. In the structure, four mol­ecules are connected by O—H⃛N bridges, forming four-membered molecular aggregates which are linked together by a complex three-dimensional hydrogen-bond network.     

Synthesis of New Functionally Substituted 1-R-tetrazoles and Their 5-Amino Derivatives

It has been shown that amino derivatives of sulfanilamide, and also some functionally substituted primary arylamines and cycloalkylamines, undergo heterocyclization with triethyl orthoformate and sodium azide with the formation of 1-monosubstituted tetrazoles. Primary amines of the azole series, 5-aminotetrazole, 5-amino-1-methyltetrazole, 4-amino-1,2,4-triazole, and also less basic arylamines (4-fluoro-3-nitroaniline, 2,6-dibromo-4-nitroaniline) did not react. An efficient method of introducing an amino group into position C₍₅₎ of the tetrazole ring of 1-aryltetrazoles is proposed, based on alkaline decomposition of the tetrazole ring and heterocyclization of the resulting N-arylcyanamides on interaction with ammonium azide generated in situ. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1174–1179, August, 2005.     

Synthesis, properties, and structure of tetrazoles: Certain achievements and prospects

The review generalizes and systematizes the results of research on the synthesis and properties of tetrazole derivatives obtained in the Belarusian State University within the last decade. The main attention is fixed on important directions in the tetrazole synthesis: the acid-catalyzed N-alkylation, the reactions of primary amines with triethyl orthoformate and sodium azide followed by the heterocyclization of imidoyl azides, and on the transformation of the obtained 1-aryltetrazoles into 1-aryl-5-aminotetrazoles. The results of quantum-chemical and X-ray investigations as well as aspects of the practical application of tetrazoles are reviewed.     

Synthesis and properties of alkyl- and phenyltetrazolium picrates

A series of tetrazolium picrates has been synthesized by quaternization of C- and N-mono substituted tetrazoles using dimethylsulfate and the systemt-BuOH/H₂SO₄ and subsequent precipitation of the cations formed with picric acid. Their thermal stability has been studied using differential scanning calorimetry and thermogravimetric analysis. An x-ray structural investigation has been carried out on 1,3-di-tert-butyl-5-methyltetrazolium picrate.Science Research Institute for Physicochemical Problems, Belorussian State University, Minsk 220080. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 657–665, May, 1998.     

Non‐linear optical crystals of 2,2,3‐tri­methyl‐3‐(1H‐1,2,3,4‐tetrazol‐5‐yl)­butane­nitrile

The title compound, C₈H₁₃N₅, is a novel functionally substituted 5‐alkyl­tetrazole. The substituent on the tetrazole C atom is symmetrical, with intrinsic symmetry close to m. There is intermolecular N—H⃛N hydrogen bonding between adjacent tetrazole rings, which is responsible for the formation of one‐dimensional polymeric chains running along the c axis. The polycrystalline compound exhibits frequency doubling for incident light (λ = 1064 nm) from a YAG:Nd pulsed laser.     

Regioselective synthesis of new functionally substituted tetrazolium salts

The 1,4-, 1,3-di- and 1,3,5-trisubstituted tetrazolium salts were obtained regioselectively and with high yields by the quaternization of 1- and 2-monosubstituted and 1,5-disubstituted tetrazoles with diacetone alcohol in perchloric acid. An X-ray crystallographic analysis of 1-(2-methylpentan-4-on-2-yl)-4-methyltetrazolium perchlorate was undertaken.Scientific-Research Institute of Physicochemical Problems, Belorus State University, Minsk; e-mail: fhp@fhp.bsu.unibel.by. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1222–1229, September, 1999.