Development of an operationally simple and metal-free protocol for the synthesis of 2-substituted-4-aminoquinazolines

Quinazolines and its analogues are well known for pharmacophores and applications for antitumor and other areas due to their proximity to DNA bases. The development of an operationally simple and efficient method for synthesizing 4-aminoquinazolines remains a key objective in organic chemistry. In this study, we present a metal-free, straightforward protocol for the construction of 2-substituted-4-aminoquinazolines using 2-methoxy-3-nitrobenzonitrile and amidines as starting materials. This method features a practical procedure, simple work-up, and the use of cost-effective reagents, providing an efficient strategy for accessing these valuable scaffolds. All the synthesized compounds were characterised through ¹H NMR, ¹³C NMR, IR and Mass spectrometry.