[Li+].CC([N-]C(C)C)C.[CH3:9][O:10][C:11]1[CH:16]=[CH:15][C:14]([C:17]2[C:18]([C:22]3[CH:29]=[CH:28][C:25]([C:26]#[N:27])=[CH:24][C:23]=3[CH3:30])=[CH:19][S:20][CH:21]=2)=[CH:13][CH:12]=1.CN(C)[CH:33]=[O:34]>O1CCCC1>[CH:33]([C:19]1[S:20][CH:21]=[C:17]([C:14]2[CH:13]=[CH:12][C:11]([O:10][CH3:9])=[CH:16][CH:15]=2)[C:18]=1[C:22]1[CH:29]=[CH:28][C:25]([C:26]#[N:27])=[CH:24][C:23]=1[CH3:30])=[O:34]A solution of freshly prepared LDA (0.8 mL, 1.64 mmol) in anhydrous tetrahydrofuran (7 mL) was added slowly a solution of 4-(4-(4-methoxyphenyl)thiophen-3-yl)-3-methylbenzonitrile (Scheme I, 3, X1=4-methoxyphenyl, X2=4-cyano-2-methylphenyl) (500 mg, 1.637 mmol) in anhydrous tetrahydrofuran (6 mL) under nitrogen at −78° C. After being stirred for 15 min., a solution of dimethylformamide (0.14 mL, 1.804 mmol) in anhydrous tetrahydrofuran (3 mL) was dropwise added. The resulting mixture was stirred for 1 h at −78° C., and at room temperature for 3 h. The reaction was quenched with water (50 mL), and extracted with ethyl acetate (40 mL×3). The combined organic extracts were washed with water (30 mL), brine (50 mL), dried over anhydrous sodium sulfate, evaporated, and purified by column chromatography (silica gel, petroleum ether/ethyl acetate=20:1) to afford 4-(2-formyl-4-(4-methoxyphenyl)thiophen-3-yl)-3-methylbenzonitrile (Scheme I, 4A, X1=4-methoxyphenyl, X2=4-cyano-2-methylphenyl) (0.16 g, yield 29.3%) as a white solid (confirmed by NOE). 1H NMR (DMSO-d6 400 MHz): δ 9.46 (s, 1H), 8.31 (d, J=1.2 Hz, 1H), 7.83 (s, 2H), 7.67 (d, J=8.8 Hz, 1H), 7.07 (d, J=8.8 Hz, 2H), 6.89 (d, J=8.8 Hz, 2H), 3.77 (s, 3H), 1.94 (s, 3H).
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