The Reaction of Nitriles with o-Aminonitriles: A Convenient Synthesis of Fused 4-Aminopyrimidines^1a,b

Synthesis of Novel Derivatives of 4-Amino-3,5-Dicyanopyrazole

“…towards nitriles. 14 The formation of pyrazoles 4, and 5 was confirmed by their 1 H NMR spectra where the signals at highest chemical shift (δ≈10-13 ppm), corresponding to the N-H in the intermediates 1 and 2, were replaced by signals at δ≈6-7 ppm, assigned to the NH 2 group of the pyrazoles. The expected pattern for the substituted phenyl ring was observed.…”

One‐pot three‐component synthesis of 2‐substituted 4‐aminoquinazolines

“…Among other methods encountered in literature, the cyclization of aromatic or aliphatic nitriles with 2-aminobenzonitrile was a frequent reaction that performed in various conditions to afford the 4-aminoquinazolines. In one of them that performed in a nearly neutral condition, despite the prolonged heating at elevated temperatures, the cyclization gave low yields of 2-alkyl and 2-aryl derivatives [18]. Strong bases [19] and acids [20] proved to facilitate the reaction; however, there are scarce examples of synthesis of the 2-alkyl derivatives in basic conditions.…”

Synthesis of Novel Derivatives of 4‐Amino‐3,5‐dicyanopyrazole.

“…towards nitriles. 14 The formation of pyrazoles 4, and 5 was confirmed by their 1 The presence of cyano groups was confirmed by two bands in their IR spectra, e.g.υ 2240 and 2224 cm -1 for compound 4a.…”