Ethyl 2-(4-chlorophenoxy)acetoacetate → Ethyl 5-chloro-3-methylbenzofuran-2-carboxylate

HRID 703058Notes

Reaction equation

HRID 703058 reaction equation
[Cl:1][C:2]1[CH:17]=[CH:16][C:5]([O:6][CH:7]([C:13]([CH3:15])=O)[C:8]([O:10][CH2:11][CH3:12])=[O:9])=[CH:4][CH:3]=1>S(=O)(=O)(O)O>[Cl:1][C:2]1[CH:17]=[CH:16][C:5]2[O:6][C:7]([C:8]([O:10][CH2:11][CH3:12])=[O:9])=[C:13]([CH3:15])[C:4]=2[CH:3]=1

Participants

3

Reactant 1

HCID 15678688Ethyl 2-(4-chlorophenoxy)acetoacetate

Product 1

HCID 15643819Ethyl 5-chloro-3-methylbenzofuran-2-carboxylateYield 65%

Reagents, catalysts & solvents 1

HCID 1118Sulfuric AcidSolvent

Conditions

Temperature
0 °C

Procedure

Ethyl 2-(4-chlorophenoxy)acetoacetate (90.3 g, 0.353 mol) was added dropwise to sulfuric acid (240 ml) stirred at 0° C. The resulting suspension was stirred at 0° C for 3.5 hours, poured onto crushed ice and the mixture stirred for 0.5 hours. The mixture was extracted with toluene and the organic phase was washed with 5% sodium bicarbonate and water. The organic phase was dried with magnesium sulfate, filtered and concentrated. The crude product was recrystallized from cyclohexane to give 54.5 g (65%) of ethyl 5-chloro-3-methyl-2-benzofurancarboxylate: mp 80°-82° C.

Workup

  1. stirringThe resulting suspension was stirred at 0° C for 3.5 hours
  2. additionpoured
  3. customonto crushed ice
  4. stirringthe mixture stirred for 0.5 hours
  5. extractionThe mixture was extracted with toluene
  6. washthe organic phase was washed with 5% sodium bicarbonate and water
  7. dry with materialThe organic phase was dried with magnesium sulfate
  8. filtrationfiltered
  9. concentrationconcentrated
  10. customThe crude product was recrystallized from cyclohexane

Sources & evidence

ORD record
ord-31b6e8ee82fa4aad8e1b25000b412153
Source dataset
uspto-grants-1991_01
Patent number
US04981849

Reaction notes

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