Ultrasound-assisted rapid synthesis of 2-aminopyrimidine and barbituric acid derivatives

Abstract

Novel, inexpensive, and relatively expeditious procedure to achieve the synthesis of different 2-aminopyrimidine and barbituric acid derivatives is presented here, starting from readily available compounds such as guanidine hydrochloride, urea, 1,3-dialkylurea, or thiourea. Under ultrasonic irradiation, base-driven (Na₂CO₃, NaOH, or NaOC₂H₅) heterocyclization reactions of the aforementioned substrates with diethyl malonate, diethyl-2-alkyl malonate, pentane-2,4-dione, or ethyl-3-oxobutanoate yielded corresponding products. Significant advantages of this sonochemical synthetic protocol with regard to the conventional thermal methods include easy reaction setup and work-up steps, reasonably mild conditions, shorter reaction times (∼30 min) and comparably high product yields. The characterization of the synthesized compounds was based on melting points, FT-IR, GC-MS, ¹H-NMR techniques, and the obtained data were also checked from the previously published studies.

Graphical Abstract

Keywords:

• 2-Aminopyrimidine
• barbituric acid
• cyclization reaction
• sonochemistry

Acknowledgment

The authors thank Dr. E. Kübra İnal for performing MS analysis.

Additional information

Funding

Mustafa Güllü and Duygu Bayramoğlu acknowledge here with the support provided by AU-BAP [15L0430001].