反応 #1851974

反応方程式

hydrogen chloride

Oxalyl chloride

3-[(4-fluorophenyl)sulfonyl]propanoic acid

AlCl3

→

6-fluoro-2,3-dihydro-4H-1-benzothiopyran-4-one

収率 93.3%

溶媒

water

dichloromethane

反応条件

後処理

1. 1
   濃縮was concentrated under reduced pressure to a residue
2. 2
   温度cooled to 0° C. in an ice bath
3. 3
   workup.ADDITIONCS2 (1 mL) was added
4. 4
   温度to warm to room temperature
5. 5
   workup.STIRRINGstirred over night
6. 6
   workup.STIRRINGstirred
7. 7
   抽出extracted with dichloromethane (3×150 mL)
8. 8
   洗浄washed with brine (1×100 mL) and water (1×100 mL)
9. 9
   乾燥dried (sodium sulfate)
10. 10
    濃縮concentrated to a yellow solid
11. 11
    その他The solid was purified by flash column chromatography on 100 g silica gel
12. 12
    洗浄eluting 10% ethyl acetate in hexanes

実験手順

3-[(4-fluorophenyl)sulfonyl]propanoic acid (3 g, 15 mmol) was dissolved in dichloromethane (30 mL ) and cooled to 0° C. in an ice bath. Oxalyl chloride (10 mL) was added slowly, dimethyl formamide (1 drop) was added and the reaction mixture was stirred at 0° C. for 0.5 hours. At which point the reaction was concentrated under reduced pressure to a residue, then resuspended in dichloromethane and cooled to 0° C. in an ice bath, CS2 (1 mL) was added and AlCl3 (4 g, 15 mmol) was added slowly. The reaction mixture was then allowed to warm to room temperature and stirred over night. Ice chips and water (250 mL) were added and stirred. Concentrated hydrogen chloride was added until pH of 2, and extracted with dichloromethane (3×150 mL). Organics were combined, washed with brine (1×100 mL) and water (1×100 mL), dried (sodium sulfate), and concentrated to a yellow solid. The solid was purified by flash column chromatography on 100 g silica gel, eluting 10% ethyl acetate in hexanes to give 6-fluoro-2,3-dihydro-4H-1-benzothiopyran-4-one (2.55 g, 93%). 1H NMR (CDCl3, 300 MHz): δ 7.80-7.76 (m, 1H), 7.27-7.23 (m, 2H), 7.15-7.09 (m, 1H), 3.23 (t, 2H, J=6.4 Hz), 2.97 (t, 2H, J=6.4 Hz) ppm.

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