| 摘要 |
NEW MATERIAL:A propiophenone derivative of formula I: (R is lower alkyl group). EXAMPLE:4, 2-Dimethyl-3-chloro-propiophenone. USE:Intermediate for synthesis of medicines, e.g. antispasmodics, etc. PROCESS:A 2-methyl-3-chloro-propionic acid halide of formula II: (X is halogen) is condensed with an alkylbenzene of formula III in the presence foa Lewis acid catalyst, e.g. aluminum chloride, antimory pentachloride, etc. at -30-20 deg.C by the Friedel-Crafts reaction to give the compound of formula I.The starting compound of formula II is obtained by addition of HCl gas to the commercially available methacrylic acid in an organic solvent, followed by the well-known method. |
