Products of the reaction of 3-halo-and 3-ethoxypropionic acids with 1, 3-dimethoxybenzene (4) in polyphosphoric acid have been shown to be 2', 4'-dimethoxy-3-(2, 4-dimethoxyphenyl)- propiophenone (6) and 1, 5-bis [3-(2, 4-dimethoxyphenyl)-3-keto-propyl]-2, 4- dimethoxybenzene (15) and these have been prepared by unambiguous syntheses. 2', 4'- Dimethoxy-3-ethoxypropiophenone (3 a) and 2', 3, 4'-trimethoxypropiophenone (3 d) have ...
