A series of 1,3-disubstituted-5,6-dihydropyrimidine-2,4-diones 1 are prepared by solid phase organic chemistry using a cyclization-cleavage strategy from readily available amines and isocyanates. An acrylate ester of Wangs resin is treated with primary amines to afford N-substituted β-aminoesters followed by treatment with isocyanates to afford β-ureido ester 4. Cyclization-cleavage of the bound ureido ester under acidic conditions gave direct formation of 5,6-dihydropyrimidinedione 1.

Reaction of polymer bound acylates with amines provides β-amino esters which can be treated with isocyanates and cyclized to give 1,3-disubstituted-5,6-dihydropyrimidine-2,4-diones.