Hydrogen Bromide → 6-Amino-2-naphthalenol

HRID 1357217Notes

Reaction equation

HRID 1357217 reaction equation
C(OC(=O)[NH:7][C:8]1[CH:17]=[CH:16][C:15]2[C:10](=[CH:11][CH:12]=[C:13]([O:18]C)[CH:14]=2)[CH:9]=1)(C)(C)C.Br>C(O)(=O)C>[NH2:7][C:8]1[CH:9]=[C:10]2[C:15](=[CH:16][CH:17]=1)[CH:14]=[C:13]([OH:18])[CH:12]=[CH:11]2

Participants

4

Reactant 2

HCID 260Hydrogen BromideHCID 57781067tert-Butyl (6-methoxynaphthalen-2-yl)carbamate

Product 1

HCID 4286056-Amino-2-naphthalenolYield 98%

Reagents, catalysts & solvents 1

HCID 176Acetic AcidSolvent

Procedure

(6-Methoxy-naphthalen-2-yl)-carbamic acid tert-butyl ester (10.05 g, 36.8 mmol), prepared in the previous step, was suspended in 300 mL of glacial acetic acid plus 200 mL of 48% HBr and under nitrogen the mixture was refluxed for 6 h. The glacial acetic acid and the 48% HBr were removed under reduced pressure and the residue partitioned between methylene chloride and water. The aqueous layer was made basic by the addition of NaHCO3. A solid precipitated. The solid was collected by filtration and dried under reduced pressure to give 6-amino-naphthalen-2-ol (5.72 g, 98%) as a gray solid, MS m/z: 160 [M+H]+.

Workup

  1. customThe glacial acetic acid and the 48% HBr were removed under reduced pressure
  2. customthe residue partitioned between methylene chloride and water
  3. additionThe aqueous layer was made basic by the addition of NaHCO3
  4. customA solid precipitated
  5. filtrationThe solid was collected by filtration
  6. customdried under reduced pressure

Sources & evidence

ORD record
ord-08ddc58b1c3343919ea29c97bda087c4
Source dataset
uspto-grants-2003_07
Patent number
US06589970B2

Reaction notes

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