Mechanical solvent-free (grinding) synthesis and characterization of new derivatives of (E)-1-(2-hydroxyphenyl)-α-methyprop-2-en-1-one and their comparative study with conventional method.

A series of three new α-methylchalcone namely (E) -3-(2'-chlorophenyl)-1-(2-hydroxyphenyl)-α-methyprop-2-en-1-one,(E)-3-(2'-ethoxyphenyl)-1-(2-hydroxyphenyl)-α-methyprop-2-en-1-one and (E)- 3-(2', 3'- dihydrobenzo-furan-5-yl)-1-(2-hydroxyphenyl)-α-methyprop-2-en-1-one were successfully synthesized by base-catalyzed Claisen-Schmidt condensation of 2-hydroxypropiophenone with various corresponding aromatic aldehydes under simple solvent-free grinding technique and conventional method. The prepared compounds were characterized by IR, 1H-NMR, 13C-NMR and MS data. The research is focused on the remarkable reaction rate achieved by the use of grinding technique which reduces the reaction time and eliminates solvents in reactions. The effectiveness of synthesis under solvent-free grinding technique is demonstrated to have shorter reaction time, mild reaction procedure, eco-friendly reaction conditions and excellent yields of the products as compared to the conventional method.