Selective N(2) alkylation of tetrazole and 5-substituted tetrazoles by alcohols

Alkylation of tetrazole and its 5-substituted derivatives by 5-tert-butyl, isopropyl, and cyclohexyl alcohols in concentrated H₂SO₄ results in high yields of the corresponding 2-alkyltetrazoles alone, irrespective of electronic properties and size of the substituent at the 5-position of the tetrazole ring. The tert-butylation of tetrazole in phosphoric acid results in the formation of a mixture of isomeric 1- and 2-substituted derivatives, the concentration of the 1-isomer increasing with decrease in the concentration of the acid in the mixture.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1643–1647, December, 1990.     

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.     

Copolymerization of styrene and 1-hexene with a TiCl<Subscript>4</Subscript>-Al(C<Subscript>6</Subscript>H<Subscript>13</Subscript>)<Subscript>3</Subscript> · Mg(C<Subscript>6</Subscript>H<Subscript>13</Subscript>)<Subscript>2</Subscript> catalytic system

The copolymerization of styrene and 1-hexene with the TiCl₄-Al(C₆H₁₃)₃ · Mg(C₆H₁₃)₂ catalytic system has been investigated. The microstructure of polymer chains, molecular-mass characteristics, and thermophysical properties of the resulting copolymers have been studied. These copolymers contain 15 to 65 mol % styrene and mostly consist of isotactic polystyrene and poly(1-hexene) blocks.     

Synthesis and properties of phenylenebis-1H-tetrazoles

Heterocyclization of m- and p-phenylenediamines with orthoformic ester and sodium azide has given phenylenebis-1H-tetrazoles. Under these conditions, o-phenylenediamine gives benzimidazole. o-, m-, and p-Phenylenebis-1H-tetrazoles were also obtained from the nitroanilines via the intermediate nitro- and aminophenyltetrazoles. The reactions of the bistetrazoles examined were basic hydrolysis, aminomethylation, and complex formation with copper salts.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1528–1532, November, 1990.     

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.     

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.