Реакция #57513

Уравнение реакции

ethanol

oxalyl chloride

resorcinol

EtMgBr

→

solid

Выход 62.0%

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

Выход 62.0%

Растворители

toluene

diethyl ether

Условия реакции

Обработка

1. 1
   ДругоеThe 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
   ДругоеMost of the solvent was evaporated
6. 6
   workup.ADDITIONEtOAc (60 mL) and water (40 mL) were added to the mixture
7. 7
   ДругоеThe layer was separated
8. 8
   Промывкаthe organic layer was washed with water (2×40 mL)
9. 9
   Сушкаdried over Na2SO4
10. 10
    Фильтрацияfiltrated
11. 11
    Концентрированиеconcentrated under reduced pressure
12. 12
    ДругоеThe residue was purified by column chromatography
13. 13
    Промывкаeluted with 20% EtOAc/hexane

Методика

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).

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