Pyrimidine derivatives and related compounds. A novel synthesis of pyrimidines, pyrazolo[4,3‐<i>d</i>]pyrimidines and isoxazolo[4,3‐<i>d</i>] pyrimidine

Abstract

Abstract Benzoylacetonitrile (II) reacted with trichloroacetonitrile (III) to yield the β‐amino‐β‐trichloromethylacrylonitrile IV. Compound IV reacted with hydrazine hydrate to yield 5‐amino‐4‐cyano‐3‐phenylpyrazole (V) and with 2‐aminopyridine to yield the aminopyridine derivative VIII ( cf ., Chart I). Compound IV reacted with III to yield 2,4‐bis(trichloromethyl)‐5‐cyano‐6‐phenylpyrimidine (I) which could be converted into a variety of pyrazolo[4,3‐ d ]pyrimidine derivatives by treatment with hydrazine hydrate under a variety of different experimental conditions ( cf ., Chart II).