반응 #1994221

반응 방정식

2

Ethyl 2,4-Bis(bromomethyl)benzoate

dioxane sulfuric acid

→

3

5-Hydroxymethylphthalide

용매

DCM

반응 조건

후처리

1. 1
   온도was heated
2. 2
   온도under reflux for 20 h
3. 3
   기타The phases were separated
4. 4
   추출the aqueous phase was extracted with DCM (5×200 mL)
5. 5
   세척The combined organic layers were washed with saturated NaHCO3 (3×200 mL) and brine (1×200 mL)
6. 6
   건조were dried over MgSO4
7. 7
   기타The solvent was removed in vacuo

실험 절차

A suspension of 2 (22.1 g, 65.7 mmol) in 700 mL of a 1:1 mixture of dioxane/sulfuric acid (1M) was heated under reflux for 20 h. After cooling to room temperature, the mixture was poured into 200 mL of DCM. The phases were separated and the aqueous phase was extracted with DCM (5×200 mL). The combined organic layers were washed with saturated NaHCO3 (3×200 mL) and brine (1×200 mL) and were dried over MgSO4. The solvent was removed in vacuo to yield 8.70 g (83%) of pure 3 as a colorless solid: 1H-NMR (400 MHz, DMSO-d6): δ 4.65 (s, 2H), 5.39 (s, 2H), 5.47 (br s, 1H), 7.51 (d, J=7.8 Hz, 1H), 7.60 (s, 1H), 7.78 (d, J=7.7 Hz, 1H); 13C-NMR (100 MHz, DMSO-d6): δ 62.4, 69.7, 120.0, 123.3, 124.5, 126.9, 147.5, 149.7, 170.5; MS (Cl+ (NH3)) m/z=165.0 (M+H+, 100), 182.0 (M+NH4+, 49).

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