Hydrochloric Acid → Ethyl 2,3-dihydro-7-nitrobenzofuran-3-on-2-ylcarboxylate

HRID 440671Notes

Reaction equation

HRID 440671 reaction equation
[H-].[Na+].[CH2:3]([O:5][C:6]([CH2:8][O:9][C:10]1(O)[C:19]([N+:20]([O-:22])=[O:21])=[CH:18][CH:17]=[CH:16][CH:11]1[C:12](OC)=[O:13])=[O:7])[CH3:4].Cl.[Cl-].[Li+]>CN(C)C=O>[N+:20]([C:19]1[C:10]2[O:9][CH:8]([C:6]([O:5][CH2:3][CH3:4])=[O:7])[C:12](=[O:13])[C:11]=2[CH:16]=[CH:17][CH:18]=1)([O-:22])=[O:21]

Participants

6

Reactant 4

HCID 313Hydrochloric AcidHCID 24758Sodium hydrideHCID 433294Lithium ChlorideHCID 67734528Methyl 2-ethoxycarbonylmethoxy-3-nitrosalicylate

Product 1

HCID 22404730Ethyl 2,3-dihydro-7-nitrobenzofuran-3-on-2-ylcarboxylate

Reagents, catalysts & solvents 1

HCID 6228DimethylformamideSolvent

Procedure

A 60% dispersion of sodium hydride in mineral oil (0.80 g, 0.020 mole) is placed in a flask, and the mineral oil is removed from it with two heptane washes. The sodium hydride is then suspended in 30 mL of N,N-dimethylformamide, and the suspension is cooled to 0°-10° C. To this suspension is added in a dropwise manner a solution of 4.53 g (0.016 mole) of methyl 2-ethoxycarbonylmethoxy-3-nitrosalicylate in 10 mL of N,N-dimethylformamide. Upon completion of addition, the reaction mixture is allowed to warm to ambient temperature at which it is stirred for approximately 16 hours. At the conclusion of this period, the reaction mixture is cooled and acidified with concentrated hydrochloric acid. Then 200 mL of a 10% aqueous solution of lithium chloride is added to the reaction mixture, and the resulting mixture is extracted three times with ethyl acetate. The combined extracts are washed with 100 mL of the 10% aqueous solution of lithium chloride, dried over anhydrous magnesium sulfate, and filtered. The filtrate is concentrated under reduced pressure, leaving a residue which is then passed through a column of silica gel, eluting with ethyl acetate. The product-containing fractions are combined, and the solvent is evaporated under reduced pressure, leaving ethyl 2,3-dihydro-7-nitrobenzofuran-3-on-2-ylcarboxylate as a residue.

Workup

  1. customthe mineral oil is removed from it with two heptane washes
  2. temperaturethe suspension is cooled to 0°-10° C
  3. additionUpon completion of addition
  4. temperatureAt the conclusion of this period, the reaction mixture is cooled
  5. extractionthe resulting mixture is extracted three times with ethyl acetate
  6. washThe combined extracts are washed with 100 mL of the 10% aqueous solution of lithium chloride
  7. dry with materialdried over anhydrous magnesium sulfate
  8. filtrationfiltered
  9. concentrationThe filtrate is concentrated under reduced pressure
  10. customleaving a residue which
  11. washeluting with ethyl acetate
  12. customthe solvent is evaporated under reduced pressure

Sources & evidence

ORD record
ord-aa3e526505c1414fa40a2a6d8941467a
Source dataset
uspto-grants-1996_05
Patent number
US05521147

Reaction notes

Loading…