Oxidative C(sp3)−N Cleavage Cascade Cyclization of N‐Uracil Amidines and Tertiaryamines: Switchable Divergent Synthesis of Functionalized Pyrimidouracils and Dihydropyrimidouracils

The divergent synthesis of dihydropyrimidouracil and pyrimidouracil derivatives from N-uracil amidines and tertiaryamines by an oxidative C(sp(3))-N cleavage cascade cyclization reaction is first described. This transformation enables the formation of new C(sp(3))-N and C(sp(2))-N bonds via the selection of different oxidation conditions. The features of this method include tunable product selectivity, excellent chemoselectivity, readily available starting materials, broad substrate scope, good tolerance of functional groups, and moderate to high yields.