Synthesis of nitrogen contaning heterocyclic compunds via one-pot reaction

Pyrimidine and fused pyrimidine derivatives, such as pyrido[2,3-d]pyrimidines have been one of the most thoroughly investigated scaffolds, and they are associated with a wide range of biological activities, such as antibacterial, antiallergic, antitumor, anti folate, tyrosine kinase, antimicrobial, calcium channel antagonists, antibacterial, anti-inflammatory, analgesic, antihypertensive, tuberculostatic, anticonvulsants, diuretic, potassium sparing and anti-aggressive activities. Several methods have already been reported for the synthesis of pyrido[2,3-d]pyrimidines and their derivatives. In recent years, as a new type of Lewis acids, rare earth metal triflate, particularly Bi(OTf)3 catalyzed organic syntheses have been developed and applied to many reactions. The most characteristic feature of triflates is that they are stable and behave as Lewis acids. Only catalytic amounts of triflates are enough to complete the reactions in most cases. Besides, they can be recovered easily after reactions and reused without loss of activity. Efficiency and environmental sustainability are major issues in modern organic chemistry. Both need to be addressed carefully when making a valuable target molecule over several distinct steps. Thus, the one-pot synthesis of a target molecule in the same reaction vessel is widely considered to be an efficient approach in synthetic organic chemistry. Recently, one pot reactions have been used to lead to the synthesis of heterocyclic scaffolds and their derivatives. In this study, substitued benzaldehyde derivatives, malononitrile and 6-amino-1,3-dimethyluracil was refluxed in the presence of EtOH by using Bi(OTf)3 as a catalyst and a series of pyrido[2,3-d]pyrimidine derivatives have been tried to synthesized via one-pot reaction. 8 compounds was synthesized. 5 of them are original compounds. Purification processes of the synthesized compounds were carried out by chromatographic methods. The structures of the obtained compounds have been clarified by spectroscopic methods such as FTIR, 1H-NMR, 13C-NMR and LCMS QTOF.