[Li][CH2:2]CCC.[Br:6][C:7]1[CH:8]=[C:9]([CH:12]=[C:13]([O:15][CH2:16][O:17][CH3:18])[CH:14]=1)[CH:10]=O.C([O-])(O)=O.[Na+]>CCOCC.[Br-].C[P+](C1C=CC=CC=1)(C1C=CC=CC=1)C1C=CC=CC=1.C1COCC1>[Br:6][C:7]1[CH:8]=[C:9]([CH:10]=[CH2:2])[CH:12]=[C:13]([O:15][CH2:16][O:17][CH3:18])[CH:14]=1A solution of n-BuLi (5.65 mL of a 1.6 M solution in Et2O, 9.04 mmol) was added dropwise to a solution of methyltriphenylphosphonium bromide (3.23 g, 9.05 mmol) in THF (15 mL) that was cooled to 0° C. The resulting yellow solution was stirred for 30 m, cooled to −78° C., and a solution of 3-bromo-5-methoxymethoxy-benzaldehyde (1.58 g, 6.46 mmol) in anhydrous THF (15 mL) was added dropwise. The mixture was slowly warmed to RT, stirred for 16 h, and then added to a saturated aqueous solution of NaHCO3 (60 mL). The layers were separated, and the aqueous layer was extracted with Et2O (2×50 mL). The combined organic layers were washed with brine (30 mL), and dried with anhydrous MgSO4. The volatile materials were evaporated, and the remaining oil was purified by flash chromatography on silica gel (0% to 3% EtOAc/hexanes) to provide 600 mg (76%) of 1-bromo-3-methoxymethoxy-5-vinyl-benzene (113c).
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