Citric acid promoted synthesis of a mini-library 2,3-dihydroquinazolin-4(1 H)-ones with good to excellent yields is achieved by tandem reaction of anthranilamides (or anthranilhydrazides) with aldehydes on grinding at room temperature under solvent-free conditions. This method has notable advantages in terms of simple workup, short reaction time, cost-effective, and environmentally benign. J. Heterocyclic Chem., (2012).