[Br:1][C:2]1[C:3]([CH3:15])=[C:4]([C:7]([OH:14])=[C:8]([C:10]([CH3:13])([CH3:12])[CH3:11])[CH:9]=1)[CH:5]=[O:6].[H-].[Na+].I[CH:19]([CH3:21])[CH3:20].O>CN(C)C=O>[Br:1][C:2]1[C:3]([CH3:15])=[C:4]([C:7]([O:14][CH:19]([CH3:21])[CH3:20])=[C:8]([C:10]([CH3:11])([CH3:12])[CH3:13])[CH:9]=1)[CH:5]=[O:6]
A stirred, cooled (ice bath) solution of 3-bromo-5-tert-butyl-6-hydroxy-2-methyl-benzaldehyde (Intermediate 140, 0.58 g, 2.14 mmol) in anhydrous N,N-dimethylformamide (10 mL) was treated with sodium hydride (0.34 g of 60% suspension in mineral oil, 8.56 mmol). After 30 minutes, 2-iodopropane (1.3 mL, 12.84 mmol) was added and the reaction mixture was heated at 75° C. overnight. The reaction mixture was then cooled and poured into iced water and extracted with diethyl ether. The organic extract was then washed with water and brine, dried over anhydrous magnesium sulfate, filtered and evaporated in vacuo to an oil. Flash column chromatography using 2–4% ethyl acetate in hexane as the eluent afforded the title product (0.43 g, 64%).
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