[F:1][C:2]1[CH:7]=[CH:6][C:5](/[C:8](/[Si](C)(C)C)=[C:9](/[C:12]2[CH:17]=[CH:16][CH:15]=[CH:14][CH:13]=2)\[CH2:10][CH3:11])=[CH:4][CH:3]=1.[Br:22]Br.C[O-].[Na+].CCOC(C)=O>C(Cl)Cl.CO>[Br:22]/[C:8](/[C:5]1[CH:6]=[CH:7][C:2]([F:1])=[CH:3][CH:4]=1)=[C:9](\[C:12]1[CH:17]=[CH:16][CH:15]=[CH:14][CH:13]=1)/[CH2:10][CH3:11]To a solution of (2) (3.93 g, 13.2 mmol) in CH2Cl2 (25 mL) at −78° C. was added bromine (2.5 g, 15.8 mmol) in 11 mL CH2Cl2 dropwise over 0.5 h. A solution of NaOMe (26.2 mmol) in methanol (36 mL) was added and the mixture was allowed to warm to rt. After stirring 3.5 h, EtOAc was added and the solution was washed with water, brine, and was dried (MgSO4) . The solvent was removed under reduced pressure and the resulting solid was recrystallized (methanol) to give the bromide (3) as a white solid (2.36 g, 59%): 1 H NMR (CDCl3) δ 7.33 (m, 7 H), 7.08 (m, 2 H), 2.33 (q, J=7.7 Hz, 2 H), 0.86 (t, J=7.7 Hz, 3 H).
불러오는 중…
