Br[CH2:2][C:3]([O:5][CH2:6][CH3:7])=[O:4].[Cl:8][C:9]1[CH:14]=[CH:13][C:12]([C:15]2([CH:18]=[O:19])[CH2:17][CH2:16]2)=[CH:11][CH:10]=1.S(=O)(=O)(O)O>C1(C)C=CC=CC=1.C(OCC)(=O)C.[Zn]>[Cl:8][C:9]1[CH:10]=[CH:11][C:12]([C:15]2([CH:18]([OH:19])[CH2:2][C:3]([O:5][CH2:6][CH3:7])=[O:4])[CH2:16][CH2:17]2)=[CH:13][CH:14]=1A mixture of zinc dust (4.0 g, 61.2 mmol), ethyl bromoacetate (6.5 mL, 58.3 mmol) and 1-(p-chlorophenyl)-cyclopropanecarboxaldehyde (10.0 g, 55.4 mmol) in toluene is stirred at 70° C. for 45 minutes, cooled with an ice-water bath, treated with 100 mL of 10% sulfuric acid, stirred at room temperature for one hour, and diluted with ethyl acetate. The organic phase is separated, washed sequentially with 10% sulfuric acid, water, 10% sodium hydrogen carbonate solution and brine, dried over anhydrous sodium sulfate, and concentrated in vacuo to obtain an oil. Chromatography of the oil using silica gel and a 9:1 to 7:3 hexanes/ethyl acetate gradient gives the title product as a colorless oil (11.3 g, 76%) which is identified by NMR spectral analyses.
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