Dimethyl Sulfate → 2-Methoxy-6-(propan-2-yl)naphthalene

HRID 1975525Notes

Reaction equation

[OH:1][C:2]1[CH:11]=[CH:10][C:9]2[C:4](=[CH:5][CH:6]=[C:7]([CH:12]([CH3:14])[CH3:13])[CH:8]=2)[CH:3]=1.[OH-].[Na+].[CH3:17]OS(OC)(=O)=O>O>[CH3:17][O:1][C:2]1[CH:11]=[CH:10][C:9]2[C:4](=[CH:5][CH:6]=[C:7]([CH:12]([CH3:14])[CH3:13])[CH:8]=2)[CH:3]=1

Participants

Conditions

Temperature: 60 °C

Procedure

To a suspension of 31.71 g 2-hydroxy-6-(1-methylethyl)naphthalene in 500 ml water and under a nitrogen atmosphere was added 61.5 g of 14.4% (by weight) sodium hydroxide (NaOH). The mixture was heated to 60° C. and 30.02 g of dimethylsulfate was added in one portion to the dark cloudy solution. In 20 minutes the pH of the reaction had dropped from 13 to 2. Another 20 g 14.4% NaOH was added. After 45 minutes 10 g additional dimethylsulfate was added. After 1 hour 20 g of 14.4% NaOH was added and the reaction was heated at 80° C. overnight. The brown suspension was then extracted with toluene and the extract was dried over magnesium sulfate (MgSO4), filtered, and concentrated in vacuum to give a crude solid which was recrystallized from isopropanol to give 2-methoxy-6-isopropylnaphthalene, melting point 63.5° to 64.5° C.

Workup

additionIn 20 minutes the pH of the reaction had dropped from 13 to 2
temperaturethe reaction was heated at 80° C. overnight
extractionThe brown suspension was then extracted with toluene
dry with materialthe extract was dried over magnesium sulfate (MgSO4)
filtrationfiltered
concentrationconcentrated in vacuum
customto give a crude solid which
customwas recrystallized from isopropanol

Sources & evidence

ORD record: ord-dea392d0f63244949da540bfeef8e20a
Source dataset: uspto-grants-1994_02
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US05286902

Reaction notes

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