I[C:2]1[C:3]([CH3:10])=[C:4]([CH:7]=[CH:8][CH:9]=1)[C:5]#[N:6].[Cl:11][CH2:12][C:13](N(OC)C)=[O:14].C([Li])CCC>C1COCC1>[Cl:11][CH2:12][C:13]([C:2]1[C:3]([CH3:10])=[C:4]([CH:7]=[CH:8][CH:9]=1)[C:5]#[N:6])=[O:14]To a solution of 3-iodo-2-methylbenzonitrile (7.71 g, 31.7 mmol) and 2-chloro-N-methoxy-N-methylacetamide (6.55 g, 47.6 mmol) in THF (100 mL) at −78° C. was added n-butyllithium (2.5 M in hexanes, 14.0 mL, 34.9 mmol) dropwise. After complete addition, the mixture was stirred 15 min. at −78° C., then quenched with the dropwise addition of 1 N HCl. The mixture was partitioned between EtOAc/water and the layers separated. The aqueous was extracted with EtOAc (2×) and the combined organic layers were washed with brine, dried (magnesium sulfate), filtered and concentrated. Recrystallization of the resulting residue from hexanes provided 3-(2-chloroacetyl)-2-methylbenzonitrile: 1H NMR (500 MHz, CDCl3), δ 7.76 (m, 2H), 7.41 (m, 1H), 4.55 (s, 2H), 2.68 (s, 3H).
読み込み中…