Syntheses of Arylcyanotriazenes and Related Compounds

Abstract

1-Aryl-3-cyanotriazene potassium salts (IIa–j) were synthesized by treating the corresponding arylazides (Ia–j) with potassium cyanide. When IIa–j were treated with dimethyl sulfate in the presence of dicyclohexyl-18-crown ether-6 (18-crown-6), methylation occurred at N1 and N3 of the triazeno group. The resulting two isomers, 1-aryl-3-cyano-1-methyltriazenes (IIIa–j) and 1-aryl-3-cyano-3-methyltriazenes (IVa–f) were all separable by means of chromatography on silica gel. However, several of the 3-isomers (IVg–j) were not isolated. On the other hand, the direct alkylation of arylcyanotriazene potassium salts (IIa, c, e) with dimethyl sulfate in methanol gave only the 1-methyl derivatives, 1-aryl-3-cyano-1-methyltriazenes (IIIa, c, e). The alkylated positions in these products were determined by chemical and spectral studies. A clear correlation between the Hammett constants and the 13C-nuclear magnetic resonance (13C-NMR) chemical shifts of the nitrile carbons of (1-aryl-3-cyano)methyl-triazenes (IIIa–j, IVa–f) was obtained. © 1982, The Pharmaceutical Society of Japan. All rights reserved.