تفاعل #1994221

معادلة التفاعل

2

Ethyl 2,4-Bis(bromomethyl)benzoate

dioxane sulfuric acid

→

3

5-Hydroxymethylphthalide

المذيبات

DCM

ظروف التفاعل

المعالجة

1. 1
   درجة الحرارةwas heated
2. 2
   درجة الحرارةunder reflux for 20 h
3. 3
   أخرىThe phases were separated
4. 4
   استخلاصthe aqueous phase was extracted with DCM (5×200 mL)
5. 5
   غسيلThe combined organic layers were washed with saturated NaHCO3 (3×200 mL) and brine (1×200 mL)
6. 6
   تجفيفwere dried over MgSO4
7. 7
   أخرىThe solvent was removed in vacuo

الإجراء التجريبي

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).

المصدر