Regioselective 4-amino-de-chlorination of trichloro- and dichloro-pyrimidines with N-sodium carbamates

4-N-Alkoxycarbonylamino-2,6-dichloro- and -2-chloro-pyrimidines have been synthesized in good to excellent regioselectivity and yields from N-sodium carbamates and, respectively, 2,4,6-trichloropyrimidine and 2,4-dichloropyrimidine, in DMF, rt, 15–30 min. The reaction is effective also with 4,6-dichloropyrimidine, producing 4-N-alkoxycarbonylamino-6-chloropyrimidines in good yields. Some conformational features of 4-N-alkoxycarbonylamino-2,6-dichloro-pyrimidines have been investigated by X-ray diffraction and 1H NMR spectroscopy.