[CH2:1]([O:8][C:9]1[CH:14]=[C:13]([O:15][CH2:16][C:17]2[CH:22]=[CH:21][CH:20]=[CH:19][CH:18]=2)[CH:12]=[CH:11][C:10]=1[OH:23])[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1.[H-].[Na+].Br[CH2:27][C:28]([O:30][CH2:31][CH3:32])=[O:29]>C1COCC1>[CH2:1]([O:8][C:9]1[CH:14]=[C:13]([O:15][CH2:16][C:17]2[CH:22]=[CH:21][CH:20]=[CH:19][CH:18]=2)[CH:12]=[CH:11][C:10]=1[O:23][CH2:27][C:28]([O:30][CH2:31][CH3:32])=[O:29])[C:2]1[CH:3]=[CH:4][CH:5]=[CH:6][CH:7]=1A mixture of 2,4-dibenzyloxyphenol (3.1 g) and sodium hydride (0.44 g, 60% dispersion in mineral oil) in THF (75 mL) is refluxed for 30 minutes then refluxing is allowed to abate. Neat ethyl bromoacetate (1.8 g) is added and refluxing continued for 1 hour. The reaction is concentrated in vacuo and the residue partitioned between ethyl acetate (100 mL) and water (100 mL). The organic phase is washed with water (100 mL), dried o ver magnesium sulphate, filtered and concentrated in vacuo to give a light brown oil. Flash chromatography of the residue eluting with dichloromethane affords ethyl 2,4-dibenzyloxyphenoxyacetate (3.2 g) after trituration with pentane.
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