Hydrogen Bromide → Methyl 8-bromo-2-naphthalenecarboxylate

HRID 259902Notes

Reaction equation

HRID 259902 reaction equation
N([O-])=O.[Na+].N[C:6]1[CH:7]=[CH:8][CH:9]=[C:10]2[C:15]=1[CH:14]=[C:13]([C:16]([O:18][CH3:19])=[O:17])[CH:12]=[CH:11]2.[BrH:20]>OS(O)(=O)=O.C(O)(=O)C.O>[Br:20][C:6]1[CH:7]=[CH:8][CH:9]=[C:10]2[C:15]=1[CH:14]=[C:13]([C:16]([O:18][CH3:19])=[O:17])[CH:12]=[CH:11]2

Participants

7

Reactant 3

HCID 260Hydrogen BromideHCID 23668193Sodium NitriteHCID 45089581Methyl 8-amino-2-naphthoate

Product 1

HCID 12068970Methyl 8-bromo-2-naphthalenecarboxylateYield 83%

Reagents, catalysts & solvents 3

HCID 176Acetic AcidSolvent2×HCID 962WaterSolventHCID 1118Sulfuric AcidSolvent2×

Conditions

Temperature
10 °C

Procedure

To a cooled (10° C.) stirred solution of NaNO2 (2.18 g, 31.5 mmol) in concentrated H2SO4 (28.3 mL) and glacial acetic acid (26.1 mL) (prepared by adding NaNO2 to cooled [10° C.] H2SO4, heating to dissolve, re-cooling and adding HOAc) was added a solution of 8-amino-2-naphthoic, methyl ester (VII) (5.72 g, 26.36 mmoles) in glacial acetic acid (88.7 mL) over 10 minutes. The resulting solution was then added slowly (over 10 minutes) to a heated (60° C.), stirred solution of CuBr (16.59 g, 43.31 mmoles) in concentrated HBr (160 mL). The mixture was warmed to 90° C. for 10 minutes, cooled, diluted with H2O (350 mL), and filtered to give 5.8 g (yield: 83%) of 8-bromo-2-naphthoic acid, methyl ester; 1H-NMR: δ9.00 (s, 1H), 8.10 (dd, J=7.5, 1.0 Hz, 1H), 7.90 (d, J=8.5 Hz, 1H), 7.85 (d, J=6.5 Hz, 2H), 7.40 (dd, J=8.2, 7.5 Hz, 1H), 4.05 (s, 3H).

Workup

  1. additionThe resulting solution was then added slowly (over 10 minutes) to
  2. temperaturea heated (60° C.)
  3. temperatureThe mixture was warmed to 90° C. for 10 minutes
  4. temperaturecooled
  5. filtrationfiltered

Sources & evidence

ORD record
ord-e41635097fbe4375b33e93478f8939a0
Source dataset
uspto-grants-1996_06
Patent number
US05523457

Reaction notes

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