2-Bromonaphthalene → 5-Bromo-2-hydroxy-alpha-(2-naphthyl)benzyl alcohol

HRID 893726Notes

Reaction equation

HRID 893726 reaction equation
[Br:1][C:2]1[CH:9]=[C:6]([CH:7]=[O:8])[C:5]([OH:10])=[CH:4][CH:3]=1.[CH:11]1[C:20]2[C:15](=[CH:16][CH:17]=[CH:18][CH:19]=2)[CH:14]=[CH:13][C:12]=1[Mg]Br.BrC1C=CC2C(=CC=CC=2)C=1.[Mg].[Cl-].[NH4+]>C(OCC)C>[Br:1][C:2]1[CH:3]=[CH:4][C:5]([OH:10])=[C:6]([CH:9]=1)[CH:7]([OH:8])[C:13]1[CH:12]=[CH:11][C:20]2[C:15](=[CH:16][CH:17]=[CH:18][CH:19]=2)[CH:14]=1

Participants

7

Reactant 5

HCID 113722-BromonaphthaleneHCID 25517Ammonium ChlorideHCID 728635-BromosalicylaldehydeHCID 5462224MagnesiumHCID 178418423HCID 178418423, compound

Product 1

HCID 537584135-Bromo-2-hydroxy-alpha-(2-naphthyl)benzyl alcoholYield 60%

Reagents, catalysts & solvents 1

HCID 3283Diethyl EtherSolvent3×

Procedure

A solution of 5-bromosalicylaldehyde (2 g) in diethyl ether (20 ml) was added to (2-naphthyl)magnesium bromide [prepared by adding a solution of 2-bromonaphthalene in diethyl ether (30 ml) to a mixture of magnesium turnings (0.49 g) and diethyl ether (20 ml) and heating the resultant mixture to reflux for 90 minutes] and the mixture was stirred at ambient temperature for 1 hour. A saturated aqueous ammonium chloride solution (20 ml) was added and the mixture was extracted with ethyl acetate (3×20 ml). The combined organic extracts were dried (MgSO4) and evaporated. The residue was purified by column chromatography using increasingly polar mixtures of petroleum ether (b.p. 60°-80° C.) and ethyl acetate as eluent to give 5-bromo-2-hydroxy-α-(2-naphthyl)benzyl alcohol (1.98 g, 60%), m.p. 115°-117° C.

Workup

  1. customprepared
  2. temperatureto reflux for 90 minutes] and the mixture
  3. extractionthe mixture was extracted with ethyl acetate (3×20 ml)
  4. dry with materialThe combined organic extracts were dried (MgSO4)
  5. customevaporated
  6. customThe residue was purified by column chromatography
  7. temperatureusing increasingly polar mixtures of petroleum ether (b.p. 60°-80° C.) and ethyl acetate as eluent

Sources & evidence

ORD record
ord-3608c89314304f2681108c386fd75b5d
Source dataset
uspto-grants-1992_06
Patent number
US05126365

Reaction notes

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