Ammonia → 5,8-Dihydro-1-naphthol

HRID 2286352Notes

Reaction equation

HRID 2286352 reaction equation
[C:1]1([OH:11])[C:10]2[C:5](=[CH:6][CH:7]=[CH:8][CH:9]=2)[CH:4]=[CH:3][CH:2]=1.C(=O)=O.N.[Li]>C(O)C>[C:1]1([OH:11])[C:10]2[CH2:9][CH:8]=[CH:7][CH2:6][C:5]=2[CH:4]=[CH:3][CH:2]=1

Participants

6

Reactant 4

HCID 222AmmoniaHCID 280Carbon DioxideHCID 70051-Naphthol2×HCID 3028194Lithium

Product 1

HCID 974665,8-Dihydro-1-naphthol

Reagents, catalysts & solvents 1

HCID 702EthanolSolvent

Procedure

108 g (0.75 mol) of α-naphthol are placed in a 4 liter reactor. The round-bottomed flask is cooled in a bath of solid carbon dioxide and alcohol, and about 1 liter of liquid ammonia is introduced, whilst stirring vigorously. When the naphthol has almost dissolved, 20.9 g of lithium wire are added in small pieces and the mixture is then stirred for 1/2 hour. 170 ml of ethyl alcohol are then poured in dropwise. The round-bottomed flask is then left to warm up and nitrogen is bubbled into the mixture in order to drive off the ammonia. The grey pasty residue is taken up in 1 liter of water and the mixture is extracted 3 times with 100 ml of ether. The aqueous phase is cooled and acidified with concentrated HC1 until the pH is acid. The brown oil which has appeared is extracted 3 times with ether and the ether fraction is washed 3 times with water before being dried over magnesium sulphate. After filtration and evaporation to dryness, the solid is taken up in ether and the mixture is dried over MgSO4 in the presence of charcoal. The mixture is filtered and the filtrate is evaporated to dryness. A yellow solid is obtained. After recrystallisation, a white solid is finally obtained. Melting point=73°-74.5° C.

Workup

  1. additionis introduced
  2. stirringthe mixture is then stirred for 1/2 hour
  3. waitThe round-bottomed flask is then left
  4. temperatureto warm up
  5. customnitrogen is bubbled into the mixture in order
  6. extractionthe mixture is extracted 3 times with 100 ml of ether
  7. temperatureThe aqueous phase is cooled
  8. concentrationwith concentrated HC1 until the pH
  9. extractionThe brown oil which has appeared is extracted 3 times with ether
  10. washthe ether fraction is washed 3 times with water
  11. dry with materialbefore being dried over magnesium sulphate
  12. filtrationAfter filtration and evaporation to dryness
  13. dry with materialthe mixture is dried over MgSO4 in the presence of charcoal
  14. filtrationThe mixture is filtered
  15. customthe filtrate is evaporated to dryness
  16. customA yellow solid is obtained
  17. customAfter recrystallisation
  18. customa white solid is finally obtained

Sources & evidence

ORD record
ord-71a2a5e2d2e040258c8f718da8aa7187
Source dataset
uspto-grants-1981_05
Patent number
US04265911

Reaction notes

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