Department of Chemistry, Annamalai University, Annamalainagar-608 002, Tamilnadu, India E-mail : drgtnarayanan@gmail.com Manuscript received 12 February 2007, revised 17 August 2007, accepted 17 December 2007 Some halogen substituted 2-propen-1-ones were synthesized by solvent free eco-friendly method. They are characterized by physical constants, analytical and spectral data. Their antifeedant activity against caster semilooper and Achoea janata L.has been studied. The chlorinated chalcones were found to be most effective.