The paper describes industrially scalable synthesis and single crystal studies of 3-cyclopropyl-3,4-dihydroquinazolin-2(1H)-one 4, a versatile intermediate in the synthesis of number of biologically active compounds. The target compound has been characterized by LC-MS, 1 H NMR and IR. The crystal structure analysis shows that the title compound crystallizes in monoclinic class under the space group P 1 21/n 1 with cell parameters, a = 10.273(2) Å, b = 8.3227(19) Å, c = 11.623(3) Å, β = 104.980(3)°, V = 960.0(4) Å 3 and Z=4.