[C:1]([CH2:3][CH2:4][C:5]1[CH:6]=[C:7]([CH:12]=C[CH:14]=1)[C:8](OC)=O)#N.CI.[CH3:17][Si](C)(C)[N-][Si](C)(C)C.[Li+].[Cl-].[NH4+:28].[C:29]([O:32][CH2:33]C)(=[O:31])[CH3:30]>O1CCCC1>[C:17]([C:7]([CH3:8])([CH3:12])[CH2:6][C:5]1[CH:14]=[C:30]([CH:1]=[CH:3][CH:4]=1)[C:29]([O:32][CH3:33])=[O:31])#[N:28]To a solution of methyl 3-(2-cyanoethyl)benzoate (510 mg, 2.70 mmol) produced in Example D43(i) in tetrahydrofuran (15 mL) was added methyl iodide (671 μL, 10.8 mmol), and a 1.1M solution (7.35 mL, 8.09 mmol) of lithium hexamethyl disilazide in tetrahydrofuran was added dropwise at −78° C. over 30 min. After the completion of the dropwise addition, the mixture was stirred at −78° C. for 1 hr. The reaction mixture was poured into a mixture of ethyl acetate (50 mL) and saturated aqueous ammonium chloride solution (50 mL), and the organic layer and the aqueous layer were separated. The aqueous layer was extracted with ethyl acetate (50 mL). The combined organic layer was washed with saturated brine (10 mL), and dried over anhydrous magnesium sulfate. The insoluble material was filtered off, and the filtrate was concentrated under reduced pressure. The obtained residue was purified by silica gel column chromatography (hexane/ethyl acetate=95/5→85/15), and the fractions containing the object product were concentrated under reduced pressure to give the title compound (260 mg, 44%) as a yellow oil.
Wird geladen…