Sulfuric Acid → HCID 178470440, compound

HRID 442335Notes

Reaction equation

HRID 442335 reaction equation
[CH2:1]([C:3]1[CH:4]=[C:5]2[C:10](=[CH:11][CH:12]=1)[N:9]=[N:8][C:7]([C:13]([O:15][CH2:16][CH3:17])=[O:14])=[C:6]2[OH:18])[CH3:2].S(=O)(=O)(O)[OH:20]>[O-2].[O-2].[O-2].[Cr+6]>[C:1]([C:3]1[CH:4]=[C:5]2[C:10](=[CH:11][CH:12]=1)[N:9]=[N:8][C:7]([C:13]([O:15][CH2:16][CH3:17])=[O:14])=[C:6]2[OH:18])(=[O:20])[CH3:2]

Participants

4

Reactant 2

HCID 1118Sulfuric AcidHCID 178470439HCID 178470439, compound

Product 1

HCID 178470440HCID 178470440, compound

Reagents, catalysts & solvents 1

HCID 10219390chromium (VI) trioxideCatalyst

Procedure

A solution of ethyl 6-ethyl-4-hydroxycinnolin-3-yl carboxylate (5.0 g.) in concentrated sulphuric acid (30 ml.) was stirred at 10° C. as chromium trioxide (6.0 g.) was added. The solution was stirred at room temperature for 5 hours and then was poured onto cracked ice. The resulting aqueous solution was extracted with ethyl acetate (4 × 250 ml.), and the combined extracts were shaken with excess sodium bisulphite solution to extract ketonic material as the bisulphite compound. The aqueous bisulphite solution was washed with ethyl acetate (2 × 250 ml.), and then treated with excess 40% v/v formaldehyde in water and sodium bicarbonate solution. The aqueous solution was extracted with ethyl acetate (3 × 250 ml.) and the combined extracts were dried (MgSO4), and filtered. Evaporation of the filtrate yielded a solid residue which on recrystallisation from a mixture of ethanol and ether gave ethyl 6-acetyl-4-hydroxycinnolin-3-yl carboxylate, m.p. 250°-252° C.

Workup

  1. additionwas added
  2. additionwas poured
  3. extractionThe resulting aqueous solution was extracted with ethyl acetate (4 × 250 ml.)
  4. stirringthe combined extracts were shaken with excess sodium bisulphite solution
  5. extractionto extract ketonic material as the bisulphite compound
  6. washThe aqueous bisulphite solution was washed with ethyl acetate (2 × 250 ml.)
  7. additiontreated with excess 40% v/v formaldehyde in water and sodium bicarbonate solution
  8. extractionThe aqueous solution was extracted with ethyl acetate (3 × 250 ml.)
  9. dry with materialthe combined extracts were dried (MgSO4)
  10. filtrationfiltered
  11. customEvaporation of the filtrate
  12. customyielded a solid residue which
  13. customon recrystallisation
  14. additionfrom a mixture of ethanol and ether

Sources & evidence

ORD record
ord-85f19789090545269d357b89a33cfd12
Source dataset
uspto-grants-1977_08
Patent number
US04045439

Reaction notes

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