| Abstract
| - Equilibrium of acylated-5-alkyloxy (aryloxy) tetrazoles and acylated-imidoyl azides was measuredby 1H NMR and/or IR spectroscopy. In nonpolar solvents the relatively weakly electron-withdrawingacyl group (CO2CH3) favored acylation at the 2-position of the 5-substituted tetrazoles. Moderatelyelectron-withdrawing groups (CO2CH2CCl3, CO2CCl3) move the equilibrium to the side of 1-acyl-5-substituted tetrazole. Strong electron-withdrawing groups (CN, SO2CH3, SO2CF3) favored theformation of the azide. The rate of isomerization of tetrazoles and the azide increases at higherconcentrations and polarity of the solvent. In solid phase or in the nonpolar solvent (diethyl ether),only one of the three isomers is present, its structure depending on the nature of the substituentsat the 1 or 2 positions of tetrazoles.
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