反応 #59121

反応方程式

aluminum trichloride

methyl 1-(2-chloro-2-oxoethyl)cyclopentanecarboxylate

hydrochloric acid

bromobenzene

→

methyl 1-[2-(4-bromophenyl)-2-oxoethyl]cyclopentane carboxylate

溶媒

ethyl acetate

Water

dichloromethane

反応条件

後処理

1. 1
   workup.ADDITIONwas slowly added
2. 2
   workup.WAITfor 12 h at rt
3. 3
   workup.ADDITIONThe reaction mixture was slowly poured into 50 mL
4. 4
   workup.STIRRINGthe mixture stirred for 30 minutes
5. 5
   その他The layers were separated
6. 6
   抽出the aqueous layer extracted with additional ethyl acetate (100 mL)
7. 7
   洗浄The combined organic layer was washed with saturated aqueous sodium chloride (100 mL)
8. 8
   乾燥dried over anhydrous sodium sulfate
9. 9
   濃縮concentrated under reduced pressure
10. 10
    その他to yield a brown oil which
11. 11
    その他was purified by flash chromatography (10:1/hexane:ethyl acetate)

実験手順

To a 150 mL flask was added dichloromethane (70 mL), methyl 1-(2-chloro-2-oxoethyl)cyclopentanecarboxylate] (3.50 g, 16.8 mmol) [prepared as described by Bajaj, et al., J. Indian Chem. Soc. 52:1076-78, 1975] and bromobenzene (2.77 g, 17.6 mmol), and the reaction mixture cooled to 0° C. before aluminum trichloride (4.77 g, 35.7 mmol) was slowly added. The mixture was stirred for 1 h at 0° C., then for 12 h at rt. The reaction mixture was slowly poured into 50 mL chilled (0° C.) 1 N aqueous hydrochloric acid solution. Water (50 mL) was added, followed by ethyl acetate (100 mL), and the mixture stirred for 30 minutes. The layers were separated and the aqueous layer extracted with additional ethyl acetate (100 mL). The combined organic layer was washed with saturated aqueous sodium chloride (100 mL), dried over anhydrous sodium sulfate, and concentrated under reduced pressure to yield a brown oil which was purified by flash chromatography (10:1/hexane:ethyl acetate) to afford methyl 1-[2-(4-bromophenyl)-2-oxoethyl]cyclopentane carboxylate as a yellow, crystalline solid (1.62 g, 30%). LC-MS ret. time 3.45 min, m/z 324.8 (MH+); 1H NMR (300 MHz, CDCl3) δ 1.50-1.83 (overlapping signals, 6H), 2.22-2.33 (m, 2H), 3.37 (s, 2H), 3.66 (s, 3H), 7.59 (d, 2H), 7.80 (d, 2H).

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