[CH3:1][O:2][C:3]1[C:10]([O:11][CH3:12])=[CH:9][CH:8]=[C:7]([OH:13])[C:4]=1[CH:5]=[O:6].Br[CH2:15][CH2:16][CH2:17][CH2:18][C:19]([O:21][CH2:22][CH3:23])=[O:20].C(=O)([O-])[O-].[K+].[K+].[I-].[Na+]>C(O)C>[CH:5]([C:4]1[C:3]([O:2][CH3:1])=[C:10]([O:11][CH3:12])[CH:9]=[CH:8][C:7]=1[O:13][CH2:15][CH2:16][CH2:17][CH2:18][C:19]([O:21][CH2:22][CH3:23])=[O:20])=[O:6]2,3-Dimethoxy-6-hydroxybenzaldehyde (5.46 g, 0.03 M), ethyl 5-bromopentanoate (6.273 g, 0.03 M), anhydrous potassium carbonate (4.45 g), sodium iodide (0.185 g) and 95% ethanol (25 ml) were reacted together in an analogous manner to that described in example 2(F) to give ethyl 5-(2-formyl-3,4-dimethoxyphenoxy)pentanoate as an oil. This ester was demethylated with magnesium iodide (from 7.18 g iodine) in an analogous manner to that described in example 2(C), except that the ethyl acetate solution obtained on work-up of the demethylation was extracted with 2 N sodium hydroxide solution. The combined extracts were acidified with conc. hydrochloric acid and the oily product extracted into ether. The combined extracts were washed with water, extracted with sodium bicarbonate solution and the combined extracts acidified to give a solid which was filtered off, washed with water and dried. The product was passed through a column of kieselgel eluting with chloroform-methanol (95:5) and the purified product was recrystallsedfrom benzene, m.p. 105°-107° C. (Found: C, 58.43; H, 3.96. C13H16O2 requires C, 58.20; H, 6.01%).
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