Pyridine → 5,6-Dihydroxy-4-nitro-2-benzofuran-1,3-dione

HRID 1881210Notes

Reaction equation

HRID 1881210 reaction equation
[OH:1][C:2]1[C:3]([N+:15]([O-:17])=[O:16])=[C:4]2[C:8](=[CH:9][C:10]=1[O:11]C)[C:7](=[O:13])[O:6][C:5]2=[O:14].[Cl-].[Al+3].[Cl-].[Cl-].N1C=CC=CC=1>C(OCC)(=O)C>[OH:1][C:2]1[C:3]([N+:15]([O-:17])=[O:16])=[C:4]2[C:8](=[CH:9][C:10]=1[OH:11])[C:7](=[O:13])[O:6][C:5]2=[O:14]

Participants

5

Reactant 3

HCID 1049PyridineHCID 6451240Aluminum(III) ChlorideHCID 866334455-Hydroxy-6-methoxy-4-nitro-isobenzofuran-1,3-dione

Product 1

HCID 159832305,6-Dihydroxy-4-nitro-2-benzofuran-1,3-dione

Reagents, catalysts & solvents 1

HCID 8857Ethyl AcetateSolvent2×

Procedure

5-Hydroxy-6-methoxy-4-nitro-isobenzofuran-1,3-dione (115 mg), aluminum chloride (80 mg) was mixed with ethyl acetate (3 ml). Pyridine (155 μl) in ethyl acetate (2 ml) was added dropwise. The resulting mixture was stirred at room temperature for 0.5 hours, heated to reflux for 3 hours, and then quenched with water (0.5 ml) and conc. HCl (0.5 ml) at 60° C. Ethyl acetate and water was removed in vacuo. The remainder was mixed with brine (2 ml) and extracted two times with ethyl acetate (15 ml). The combined organic layers were dried over anhydrous Na2SO4, filtrated, evaporated and triturated with diethyl ether.

Workup

  1. temperatureheated
  2. temperatureto reflux for 3 hours
  3. customquenched with water (0.5 ml) and conc. HCl (0.5 ml) at 60° C
  4. customEthyl acetate and water was removed in vacuo
  5. additionThe remainder was mixed with brine (2 ml)
  6. extractionextracted two times with ethyl acetate (15 ml)
  7. dry with materialThe combined organic layers were dried over anhydrous Na2SO4
  8. filtrationfiltrated
  9. customevaporated
  10. customtriturated with diethyl ether

Sources & evidence

ORD record
ord-f8a916d1eb674a33968be81d16f22307
Source dataset
uspto-grants-2012_11
Patent number
US08318785B2

Reaction notes

Loading…