Dimethyl Sulfate → 7-Methoxy-2-naphthol

HRID 402109

Reaction equation

HRID 402109 reaction equation
[OH-].[Na+].S([O:8][CH3:9])(OC)(=O)=O.[OH:10][C:11]1[CH:20]=[CH:19][C:18]2[C:13](=[CH:14][C:15](O)=[CH:16][CH:17]=2)[CH:12]=1>ClCCl.O>[OH:10][C:11]1[CH:20]=[CH:19][C:18]2[C:13](=[CH:14][C:15]([O:8][CH3:9])=[CH:16][CH:17]=2)[CH:12]=1

Participants

6

Reactant 3

HCID 6497Dimethyl Sulfate2×HCID 113972,7-NaphthalenediolHCID 14798Sodium Hydroxide2×

Product 1

HCID 8531737-Methoxy-2-naphtholYield 30.1%

Reagents, catalysts & solvents 2

HCID 962WaterSolventHCID 6344DichloromethaneSolvent

Procedure

Sodium hydroxide (20 ml, 1M) and dimethyl sulfate (15.0 ml, 158 mmol) were added dropwise to a solution of 2,7-dihydroxynaphthalene (6.6 g, 40 mmol) in dichloromethane (100 ml) and water (60 ml). Additional sodium hydroxide (20 ml, 1M) and dimethyl sulfate (15.0 ml, 158 mmol) were added and the resulting mixture was stirred at room temperature for 2 hours. The two phases were separated and the aqueous layer was extracted with dichloromethane twice. The combined organic extracts were washed with 1 M HCl, dried over magnesium sulfate and concentrated under vacuum. The crude material was purified by column chromatography (5:1 heptane/ethyl acetate) to give 2-hydroxy-7-methoxynaphthalene (2.1 g, 30%, 100% AUC HPLC): 1H NMR (300 MHz, CDCl3) δ 7.66-7.70 (m, 2H), 6.94-7.08 (m, 4H), 4.90 (s, 1H), 3.92 (s, 3H).

Workup

  1. customThe two phases were separated
  2. extractionthe aqueous layer was extracted with dichloromethane twice
  3. washThe combined organic extracts were washed with 1 M HCl
  4. dry with materialdried over magnesium sulfate
  5. concentrationconcentrated under vacuum
  6. customThe crude material was purified by column chromatography (5:1 heptane/ethyl acetate)

Sources & evidence

ORD record
ord-054b4efe03314193b34ec2575f0b1608
Source dataset
uspto-grants-2014_06
Patent number
US08741901B2

Linked notes

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