Methylation of 5-nitrotetrazole sodium salt under phase-transfer catalysis conditions

Abstract

The alkylation of 5-nitrotetrazole sodium salt with dimethyl sulfate was studied in a two-phase water–dichloromethane system in the presence of tetrabutylammonium bromide as a phase-transfer catalyst. The reaction produced a mixture of regioisomers – 1-methyl- and 2-methyl-5-nitrotetrazoles in 1:3 ratio. 2-Methyl-5-nitrotetrazole was obtained from this mixture as individual compound in 52% yield. The application of phase-transfer catalysis allowed to obtain 5-nitrotetrazole N-alkyl derivatives under conditions that did not require preliminary isolation of highly impact and friction sensitive 5-nitrotetrazole salts from aqueous solutions.