HETEROCYCLIC STUDIES .12. TRICHLORO-6-CYANOPYRIMIDINE

Treatment of 4-carbamoyl-2,6-dihydroxy-5-nitropyrimidine (I; X=CONH 2) with phosphoryl chloride and diethylaniline unexpectedly yielded 2,4,5-trichloro-6-cyanopyrimidine (III: X=CN) together with 4-carbamoyl-2,6- dichloro-5-nitropyrimidine (II; X=Cl,Y=CONH2) and a little 2-chloro-4-cyano-6-N-ethylanilino-5-nitro-pyrimidine (II; X=NEtPh, Y=CN). Some of the trichloro-cyano-pyrimidine was also obtained by treatment of the pyrimidine (I; X=CONH2) with phosphoryl chloride in the presence of dimethylaniline, pyridine, triethylamine, or phosphorus pentachloride. Nucleophilic substitution reactions of trichloro-6-cyanopyrimidine, in which the cyano-group was often displaced first, or modified, are described.