[Br:1][C:2]1[CH:3]=[C:4]2[C:9](=[CH:10][CH:11]=1)[N:8]([CH:12]=O)[CH2:7][CH2:6][C:5]2([CH3:15])[CH3:14].[CH2:16]([Mg]Br)[CH3:17].C(OCC)C>O1CCCC1>[Br:1][C:2]1[CH:3]=[C:4]2[C:9](=[CH:10][CH:11]=1)[N:8]([CH:12]1[CH2:17][CH2:16]1)[CH2:7][CH2:6][C:5]2([CH3:15])[CH3:14]A stirred, cooled (0° C.) solution of 6-bromo-4,4-dimethyl-1,2,3,4-tetrahydro-quinoline-1-carbaldehyde (Intermediate 50, 21.8, 6.7 mmol) in anhydrous tetrahydrofuran (20 mL) under argon was treated with titanium tetra-iso-propoxide (2.15 mL, 7.39 mmol) followed by 3M solution of ethyl magnesium bromide in diethyl ether (5.6 mL, 16.8 mmol) and the reaction mixture was then heated at 50° C. overnight. It was then cooled in an ice-bath, quenched with saturated aqueous ammonium chloride solution and extracted with diethyl ether (×2). The combined organic phase was dried over anhydrous sodium sulfate, filtered over celite and evaporated in vacuo to residue which was subjected to flash column chromatography over silica gel (230-400 mesh) using 5% ethyl acetate in hexane as the eluent to afford the title compound as an oil (1.2 g, 64%).
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