反応 #57513

反応方程式

ethanol

oxalyl chloride

resorcinol

EtMgBr

→

solid

収率 62.0%

(2,4-Dihydroxy-phenyl)-oxo-acetic acid ethyl ester

収率 62.0%

溶媒

toluene

diethyl ether

反応条件

後処理

1. 1
   その他The ether was removed under vacuum and anhydrous toluene (80 mL)
2. 2
   workup.ADDITIONwas added
3. 3
   workup.STIRRINGThe reaction mixture was stirred at rt for 15 h
4. 4
   workup.STIRRINGthe reaction mixture was stirred at rt for 1 h
5. 5
   その他Most of the solvent was evaporated
6. 6
   workup.ADDITIONEtOAc (60 mL) and water (40 mL) were added to the mixture
7. 7
   その他The layer was separated
8. 8
   洗浄the organic layer was washed with water (2×40 mL)
9. 9
   乾燥dried over Na2SO4
10. 10
    ろ過filtrated
11. 11
    濃縮concentrated under reduced pressure
12. 12
    その他The residue was purified by column chromatography
13. 13
    洗浄eluted with 20% EtOAc/hexane

実験手順

To a solution of resorcinol (5.0 g, 45.4 mmol, 1 eq) in diethyl ether (30 mL) was added 3M EtMgBr (18.5 mL, 50.0 mmol, 1.1 eq)) dropwise under argon. The reaction mixture was stirred at rt for 20 min. The ether was removed under vacuum and anhydrous toluene (80 mL) was added. A solution of oxalyl chloride (4.36 mL, 50 mmol, 1.1 eq) in toluene (20 mL) was added to the mixture dropwise under argon. The reaction mixture was stirred at rt for 15 h. Anhydrous ethanol (40 mL) was added to the mixture and the reaction mixture was stirred at rt for 1 h. Most of the solvent was evaporated and then EtOAc (60 mL) and water (40 mL) were added to the mixture. The layer was separated and the organic layer was washed with water (2×40 mL), dried over Na2SO4, filtrated, and concentrated under reduced pressure. The residue was purified by column chromatography eluted with 20% EtOAc/hexane then 50% EtOAc/hexane solution to afford white solid (5.88 g, 62%) as product. 1H-NMR (CD3CN): δ 7.62(d, J=9.0 Hz, 1H), 6.50 (dd, J=2.3, 9.0 Hz, 1H), 6.41 (d, J=2.3 Hz, 1H), 4.44 (q, 2H), 1.40 (t, 3H).

出典