Studies with Polyfunctionally Substituted Heteroaromatics: The Reaction of Heterocyclic Enaminonitriles with α‐β‐Unsaturated Nitriles

Abstract

5‐Amino‐4‐cyano‐3‐phenylpyrazole (1) reacts with cinnamonitriles (2) to yield the pyrazolo[1,5‐a]pyrimidines (3). Also, 5‐amino‐4‐cyano‐1‐phenylpyrazole (4) reacts with cinnamonitriles (2) to yield the pyrazolo[3,4‐b]pyridine derivatives (5). In contrast to this reaction, enaminothiophene (6) reacts with cinnamonitriles (2) to yield compound (7) not (8). The enaminopyrane (9) reacts with cinnamonitriles (2) to yield (10). Finally we have attempted to add cinnamonitriles (2) to thiopyrane (13); only rearrangement and aromatization product (14) was isolated.