Synthesis of Pyrimidines and Pyrimidones

Marzinzik and Felder [34] used polymer-bound enones which were generated from 4-carboxybenzaldehyde immobilized on Rink amide resin for the synthesis of pyrimidines and pyrimidones.The enones were then treated with different amidines in DMA for 16 h at 100°C (Fig. 6.25). 

The isolated yields of the pyrimidines ranged from 58% to 98%, with HPLC purities of 95 %. By using N-methylurea in the presence of NaOEt, a dihydropyrimidone with a purity of 94% and an isolated yield of 84% was obtained as a single regioisomer (Fig. 6.25b, c). 

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