Water ultrasound-assisted oxidation of 2-oxo-1,2,3,4-tetrahydropyrimidines and benzylic acid salts

Abstract

© 2018, Springer International Publishing AG, part of Springer Nature. Nitrogen six-membered heterocyclic compounds, such as pyrimidines, are of synthetic interest because they constitute an important class of natural and synthetic products. 2-oxo-1,2,3,4-tetrahydropyrimidines are important drugs which have shown broad spectrum activities such as inhibitory against human immunodeficiency virus (HIV) replication, antimitotic, antiproliferative, and cytotoxic activities. Their derivatization involves the oxidation of C(sp3)-H bonds and is a major reaction for making double bonds in synthetic chemistry and biological systems. However, actual methods use toxic solvents or require strictly anhydrous conditions. As a consequence, there is a need for new and environmental benign protocols. Here we present water ultrasound oxidation of the benzylic position in 2-oxo-1,2,3,4-tetrahydropyrimidines and benzylic acid salts, into double bond using heterogeneous oxidizing agents Cu(III) or Ag(III). This method has several advantages such as the use of green solvent, broad substrate scope, excellent yields and less amounts of waste with excellent values of green chemistry metrics.