T. V. Artamonova

Tetrazoles: LI. Synthesis of 5-substituted tetrazoles under microwave activation

Reaction of nitriles with sodium azide in the presence of ZnCl2 under microwave activation (MWA) leads to the formation of 5-tetrazoles in high yields; therewith the process is 2–3 times shorter than the inactivated reaction.

Tetrazoles: LII. Synthesis of functionally substituted tetrazoles from benzene-1,3,5-tricarboxylic acid derivatives

N,N′,N″-Triarylbenzene-1,3-5-tricarboximidoyl chlorides reacted with sodium azide under conditions of phase-transfer catalysis to give functionally substituted tetrazoles whose subsequent functionalization led to complex heterocyclic structures which may be regarded as first-generation tetrazole-containing dendrimers.

Tetrazoles: XLIX. Alkylation of tetrazoles with tetrakis(chloroacetoxymethyl)methane

Alkylation of 1-aryl-4,5-dihydro-1H-tetrazol-5-ones and 1-phenyl-4,5-dihydro-1H-tetrazole-5-thione with tetrakis(2-chloroacetoxymethyl)methane in boiling acetonitrile in the presence of potassium bromide and triethylamine gives tetrakis[2-(4-aryl-5-oxo-4,5-dihydro-1H-tetrazol-1-yl)acetoxymethyl]-methanes and tetrakis[2-(1-phenyl-1H-tetrazol-5-ylsulfanyl)acetoxymethyl]methane, respectively. The alkylation process is considerably accelerated under microwave irradiation.

Tetrazoles: XLVI. Alkylation of 5-substituted tetrazoles with methyl chloromethyl ether and α-methylstyrene

Alkylation of 5-aryl(hetaryl)tetrazoles with methyl chloromethyl ether under conditions of phase-transfer catalysis leads to formation of isomeric 1- and 2-methoxymethyltetrazoles at a ratio of ~1 : 2. The reaction of 5-substituted tetrazoles with α-methylstyrene in the presence of trichloroacetic acid gives the corresponding 2-(α,α-dimethylbenzyl)tetrazoles in high yield and with high regioselectivity.

Tetrazoles: L.* Microwave-Activated Alkylation of 5-Aryltetrazoles and 1-Substituted Tetrazole-5-thiones with 1,3-Dibromo-2,2-bis(bromomethyl)propane

Alkylation of 5-aryltetrazoles and 1-substituted tetrazole-5-thiones with 1,3-dibromo-2,2-bis(bromomethyl)propane in dimethylformamide in the presence of sodium hydroxide leads to the formation of tetrakis(5-aryltetrazol-2-ylmethyl)methanes and tetrakis(1-R-tetrazol-5-ylsulfanylmethyl)methanes, respectively. Microwave activation considerably shortens the reaction time and increases the yield.

Tetrazoles: XLIII. Polydentate Tetrazole-Containing Ligands for Biomimetic Studies

Abstract1(2)-Aryl-5-methylsulfonyltetrazoles react with ethylene glycol, di- and triethylene glycols, and tris(2-hydroxyethyl)amine in acetonitrile in the presence of sodium hydroxide to give tetrazole-containing ethers. The products can be used as polydentate ligands for biomimetic studies.

Reactions of 5-Methylsulfinyl-1-(4-nitrophenyl)tetrazole with N-Nucleophiles

Wide application of tetrazoles in the synthesis of new medical agents for various purposes [1–7] stimulated extensive search for simple and effective procedures for functionalization of these compounds. While continuing our studies on 1-aryltetrazole-5-thiones as readily accessible synthons for the preparation of functionally substituted tetrazoles, we examined the reactivity of 5-methylsulfinyl-1-(4-nitrophenyl)tetrazole with respect to various nitrogen-centered nucleophiles. Initial 5-methylsulfinyl-1-(4-nitrophenyl)tetrazole (I) was synthesized by oxidation of 5-methylsulfanyl-1(4-nitrophenyl)tetrazole with 35% hydrogen peroxide in acetic acid at 70°C (Scheme 1). Under these conditions, compound I was formed in almost quantitative yield. The rate of oxidation considerably increases under microwave irradiation, while the yield of tetrazole I remains almost unchanged.