An efficient and convenient multi component reaction for the synthesis of 2-Imino-4,6-diaryldihydropyrimidines scaffolds have been accomplished from chalcones and guanidine hydrochloride in the presence of a catalytic amount of an alkali under solvent-free conditions using microwave irradiation.  The synthesized pyrimidines have been characterized on the basis of their chemical properties and spectroscopic data.  Operational simplicity, short reaction times, excellent yields and environmentally-benign conditions are the other advantages of this protocol. Using this method, we have synthesized some new pyrimidines with antimicrobial properties and high chemical yields in much short reaction times.