Br[CH2:2][C:3]1[CH:8]=[CH:7][CH:6]=[CH:5][C:4]=1[C:9]([CH3:19])([CH3:18])[CH2:10][C@:11]1([C:14]([F:17])([F:16])[F:15])[CH2:13][O:12]1.C(=O)(O)[O-:21].[Na+]>CS(C)=O.[Cl-].[NH4+]>[CH3:18][C:9]([C:4]1[CH:5]=[CH:6][CH:7]=[CH:8][C:3]=1[CH:2]=[O:21])([CH3:19])[CH2:10][C@:11]1([C:14]([F:17])([F:16])[F:15])[CH2:13][O:12]1To a stirred solution of (R)-2-[2-(2-bromomethylphenyl)-2-methylpropyl]-2-trifluoromethyloxirane (46.6 g, 0.138 mol) in 300 mL of DMSO was added sodium bicarbonate (24 g, 0.285 mol) and the reaction mixture was heated to 70° C. After 24 hours, the reaction mixture was cooled to normal room temperature, diluted with 1200 mL of saturated aqueous ammonium chloride solution and extracted with four 250 mL portions of diethyl ether. The combined diethyl ether extracts were washed with brine, dried over anhydrous sodium sulfate, and the solvent evaporated in vacuo. The crude material was purified by column chromatography over silica gel (400 g) eluting with 0-15% ethyl acetate in hexanes and fractions corresponding to the major peak were pooled and solvent removed in vacuo to give 2-[1,1-dimethyl-2-((R)-2-trifluoromethyloxiranyl)ethyl]benzaldehyde as a light yellow oil (20 g, 62%).
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