[Cl:1][C:2]1[CH:14]=[CH:13][CH:12]=[CH:11][C:3]=1[O:4][CH2:5][C:6]([O:8][CH2:9][CH3:10])=[O:7].[C:15]1(=[O:21])[O:20][C:18](=[O:19])[CH2:17][CH2:16]1.[Cl-].[Cl-].[Cl-].[Al+3].Cl>ClCCl.CCCCCC.O>[Cl:1][C:2]1[CH:14]=[C:13]([C:15](=[O:21])[CH2:16][CH2:17][C:18]([OH:20])=[O:19])[CH:12]=[CH:11][C:3]=1[O:4][CH2:5][C:6]([O:8][CH2:9][CH3:10])=[O:7]
To a stirred solution of ethyl 2-chlorophenoxyacetate (32.0 g, 149 mmol) in dichloromethane (75 mL) at ambient temperature under nitrogen was added succinic anhydride (22.4 g, 224 mmol). The reaction mixture was cooled in ice-water and to this was added portion wise aluminum trichloride (59.6 g, 447 mmol), whilst maintaining the temperature below 20° C. The reaction mixture was then allowed to stir at ambient temperature for 20 minutes and was then heated to reflux and stirred at this temperature for 3 hours. The reaction mixture was allowed to cool to ambient temperature, then poured into a mixture of ice, water (200 ml) and HCl (10 N, 100 ml). The two phase system was separated and the aqueous layer was extracted with ethyl acetate (5×100 mL). All organic layers were then combined and washed with water (2×100 mL), dried over Na2SO4, and concentrated under reduced pressure to give an orange oily solid. Hexane (300 mL) was added, and after standing at ambient temperature for 1 hour, the precipitate was filtered off and re-crystallized from ethyl acetate/hexane to give 9 as a light yellow powder (21.5 g, 46% yield, 98% pure by LCMS and 1H NMR), 1H NMR (400 MHz; CDCl3): δ 7.79 (m, 1H); 7.66 (m, 1H); 6.79 (m, 1H); 4.90 (s, 2H); 4.12 (q, 2H); 2.82 (m, 2H); 2.42 (m, 2H); 1.30 (t, 3H).
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