반응 #7105

반응 방정식

3-bromo-2-fluorobenzoic acid

trimethylorthoformate

p-toluenesulfonic acid

→

methyl 3-bromo-2-fluorobenzoate

수율 84.0%

용매

methanol

반응 조건

후처리

1. 1
   온도heated
2. 2
   온도under reflux
3. 3
   기타the mixture was evaporated
4. 4
   기타the residue partitioned between water and Et2O
5. 5
   세척The organic layer was washed with sat. sodium hydrogen carbonate solution, water, brine
6. 6
   건조dried (MgSO4)
7. 7
   기타evaporated

실험 절차

A solution of 3-bromo-2-fluorobenzoic acid (0.219 g, 1 mmol) in dry methanol (5 ml) under nitrogen was treated with trimethylorthoformate (0.22 ml, 2 mmol) and p-toluenesulfonic acid (catalytic amount), and then heated under reflux. After 16 h, the mixture was evaporated and the residue partitioned between water and Et2O. The organic layer was washed with sat. sodium hydrogen carbonate solution, water, brine, dried (MgSO4) and evaporated to give methyl 3-bromo-2-fluorobenzoate (0.195 g, 0.84 mmol, 84%): 1H NMR (CDCl3) δ 7.90–7.85 (m, 1H), 7.71–7.65 (m, 1H), 7.10 (dt, 1H, J=8.0, 1.0 Hz) and 3.94 (s, 3H): MS (EI) 232 (M+).

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