NOVEL 2H-1,2,3-TRIAZOLE SODIUM COMPLEX FROM N-2-AMINO-1,2-DICYANOVINYLALKANAMIDES

摘要

Diazotization at 0 °C of N-2-amino-1,2-dicyanovinylethanamide 2a or propanamide 2b prepared from diaminomaleonitrile(DAMN)1 using aqueous acetic acid and NaNO2 solution furnished sodium complex 3.The X-ray structure of the complex 3 showed that it is a 1:1 mixture of the neutral 2H-triazole heterocycle 4ii and its anion deprotonated at the central(N)atom of the ring,together with a sodium counter ion and two coordinated water molecules.However,when the diazotization reaction was carried out in the presence of aqueous HCl,the product was 5-cyano-2H-1,2,3triazole-4-carboxylic acid amide monohydrate 4ii.Diazotization of DAMN 1 using aqueous HCl furnished 1H-1,2,3-triazole-4,5-dicarbonitrile 5,whereas with acetic acid there was no reaction,and hence no route analogous to that leading to complex 3.The structure of both complex 3 and the triazole monohydrate 4ii were solved using X-ray crystallography,and the compounds under study were fully characterized using spectroscopic techniques.