ABSTRACT
A practical, mild, and high-yielding synthetic approach for the synthesis of unknown tetrahydropyrimidinyl substituted 3-coumarins as hybrid scaffolds, potentially useful new chemical entities (NCEs), via metal- and catalyst-free multicomponent cyclization is described. The enhanced nucleophilicity of 3-amino coumarins versus 4-amino coumarin is explained via the difference in 13C NMR δ values (Δδ) of vinylic carbons. X-ray crystal analysis defines the structure of a representative set of example.
GRAPHICAL ABSTRACT
Acknowledgment
The authors are thankful to the head of the Department of Chemistry, Saurashtra University, Rajkot, for providing facilities.