Aminolysis of Methoxy Groups in Pyrimidine Derivatives. Activation by 5-Nitroso Group

The nucleophilic substitution of 2-methoxy groups in pyrimidine derivatives was strongly activated by introduction of a 5-nitroso group on to the pyrimidine ring. The aminolysis of several 2-methoxy-5-nitrosopyrimidine derivatives was performed at room temperature in hydroxylic as well as in non-hydroxylic media with different primary amines in short time and good yields. The aminolysed substrates include 6-[(per-O-acetyl)glycosyl]aminopyrimidines which afforded the corresponding 2-aminopyrimidines without harming the acetyl protecting groups of the sugar moiety.