Chemistry of 5‐pyrimidinecarboxaldehydes

Selective hydrolysis of 2‐amino‐4,6‐dichloro‐5‐pyrimidinecarboxaldehyde, 2 , gave 2‐amino‐4‐chloro‐1,6‐dihydro‐6‐oxo‐5‐pyrimidinecarboxaldehyde, 5 . The oxime of 2 rearranged to 2‐amino‐4‐chloro‐1,6‐dihydro‐6‐oxo‐5‐pyrimidinecarbonitrile, 8 . Reaction of 8 with 4‐phenylbutylamine resulted in the displacement of the 4‐chloro atom to give compound 9 . Hydrolysis of the cyano function of 9 gave amides 12 , 13 , and 14 depending on reaction conditions. A discussion of the 1H‐nmr spectrum of 2‐amino‐1,6‐dihydro‐6‐oxo‐4‐[(4‐phenylbutyl)amino]‐5‐ pyrimidinecarboxaldehyde, 6 , is presented.