5,8-Dihydro-5-ethyl-8-oxofuro-[3,2-b]-1,8-naphthyridine-2,7-dicarboxylic acid → DJ 6783

HRID 847778

Reaction equation

HRID 847778 reaction equation
[CH2:1]([N:3]1[C:12]2[N:11]=[C:10]3[CH:13]=[C:14](C(O)=O)[O:15][C:9]3=[CH:8][C:7]=2[C:6](=[O:19])[C:5]([C:20]([OH:22])=[O:21])=[CH:4]1)[CH3:2]>[Cu].C(OCC)(=O)C1C(=CC=CC=1)C(OCC)=O>[CH2:1]([N:3]1[C:12]2[N:11]=[C:10]3[CH:13]=[CH:14][O:15][C:9]3=[CH:8][C:7]=2[C:6](=[O:19])[C:5]([C:20]([OH:22])=[O:21])=[CH:4]1)[CH3:2]

Participants

4

Reactant 1

HCID 128750245,8-Dihydro-5-ethyl-8-oxofuro-[3,2-b]-1,8-naphthyridine-2,7-dicarboxylic acid

Product 1

HCID 175411DJ 6783Yield 51.7%

Reagents, catalysts & solvents 2

HCID 23978CopperCatalystHCID 6781Diethyl PhthalateSolvent

Procedure

A mixture of 9.5 g of 5,8-dihydro-5-ethyl-8-oxofuro-[3,2-b]-1,8-naphthyridine-2,7-dicarboxylic acid (Compound X where R1 =C2H5), 0.8 g of copper powder and 250 ml of diethyl phthalate was heated at 250° to 260° C. for 25 minutes. After cooling, the reaction mixture was separated by partitioning between chloroform and aqueous potassium carbonate solution. The aqueous layer which separated out was acidified with hydrochloric acid and extracted with chloroform. The extract was treated with charcoal, and washed with water, dried and concentrated. The crystals precipitated by adding ethanol were collected by filtration to obtain 4.2 g of 5,8-dihydro-5-ethyl-8-oxofuro[3,2-b]-1,8-naphthyridine-7-carboxylic acid (Compound Ia where R1 =C2H5).

Workup

  1. temperaturewas heated at 250° to 260° C. for 25 minutes
  2. temperatureAfter cooling
  3. customthe reaction mixture was separated
  4. customby partitioning between chloroform and aqueous potassium carbonate solution
  5. customThe aqueous layer which separated out
  6. extractionextracted with chloroform
  7. additionThe extract was treated with charcoal
  8. washwashed with water
  9. customdried
  10. concentrationconcentrated
  11. customThe crystals precipitated
  12. additionby adding ethanol
  13. filtrationwere collected by filtration

Sources & evidence

ORD record
ord-4e5eec42a8134bec9b82deb1793f41ad
Source dataset
uspto-grants-1981_10
Patent number
US04293695

Linked notes

Loading…