N,N-cyclization of carbodiimides with 2-(bromomethyl)acrylic acid. a direct entry to the system 5-methylene-6H-pyrimidine-2,4-dione, a new class of thymine analogues

Article abstract of DOI:10.1002/jhet.5570330444

Carbodiimides react under very mild conditions with 2-(bromomethyl)acrylic acid at both N atoms to give 1,3-disubstituted-5-methylene-6ff-pyrimidine 2,4-dione derivatives in moderate to good yields. These products behaved as good Michael acceptors towards a variety of nucleophiles such as bromine, hydrochloric acid, hydrides, etc. A plausible mechanism is proposed based on theoretical approaches and experimental results.