tert-Butanol → Methyl 2-methoxy-1-(3-methylbutyl)-1,4-dihydronaphthalene-1-carboxylate

HRID 494655

Reaction equation

HRID 494655 reaction equation
[CH3:1][O:2][C:3]1[CH:12]=[CH:11][C:10]2[C:5](=[CH:6][CH:7]=[CH:8][CH:9]=2)[C:4]=1[C:13]([O:15][CH3:16])=[O:14].C(O)(C)(C)C.[K].[CH2:23](I)[CH2:24][CH:25]([CH3:27])[CH3:26]>N>[CH3:1][O:2][C:3]1[C:4]([CH2:23][CH2:24][CH:25]([CH3:27])[CH3:26])([C:13]([O:15][CH3:16])=[O:14])[C:5]2[C:10]([CH2:11][CH:12]=1)=[CH:9][CH:8]=[CH:7][CH:6]=2

Participants

6

Reactant 4

HCID 6386tert-ButanolHCID 109241-Iodo-3-methylbutaneHCID 604022Methyl 2-methoxy-1-naphthoateHCID 5462222Potassium

Product 1

HCID 68838307Methyl 2-methoxy-1-(3-methylbutyl)-1,4-dihydronaphthalene-1-carboxylateYield 85%

Reagents, catalysts & solvents 1

HCID 222AmmoniaSolvent

Procedure

To a stirred solution of methyl 2-methoxynaphthoate (1.0 g, 4.6 mmol) and tert-butyl alcohol (0.44 ml, 4.6 mmol) at −78° C. was added liquid ammonia (20 mL). Potassium metal was added in small pieces until the solution stayed dark blue for 30 min. Isoamyl iodide (1.9 mL, 14.8 mmol) was added dropwise (the blue coloration disappeared about half-way through addition) and stirring was continued for 1 hour at −78° C. The solution was allowed to warm to room temperature and purged with nitrogen to remove excess ammonia. To the resulting slurry a solution of saturated sodium bicarbonate (100 mL) was added, and the solution was extracted with ether (3× 50 mL). The combined organic phases were washed with 10% Na2S2O3 (aq), dried (Na2SO4), and concentrated in vacuo. Column chromatography on silica (5%-15% ethyl acetate/hexane) afforded product as a light yellow oil (1.1 g, 85%). 1H NMR (300 MHz, CDCl3) δ ppm 0.55 (m, 1H), 0.75 (dd, J=14.71, 6.62 Hz, 6H), 0.88 (m, 1H), 1.39 (m, 1H), 2.06 (m, 1H), 2.27 (m, 1H), 3.55 (d, J=3.31 Hz, 2H), 3.60 (s, 3H), 3.61 (s, 3H), 5.05 (t, J=3.68 Hz, 1H), 7.16 (m, 4H); MS m/z 289.0 (M+H)+.

Workup

  1. additiondisappeared about half-way through addition) and
  2. waitwas continued for 1 hour at −78° C
  3. custompurged with nitrogen
  4. customto remove excess ammonia
  5. additionTo the resulting slurry a solution of saturated sodium bicarbonate (100 mL) was added
  6. extractionthe solution was extracted with ether (3× 50 mL)
  7. washThe combined organic phases were washed with 10% Na2S2O3 (aq)
  8. dry with materialdried (Na2SO4)
  9. concentrationconcentrated in vacuo

Sources & evidence

ORD record
ord-059051561daf4d53b68964db6f81768c
Source dataset
uspto-grants-2009_05
Patent number
US07538105B2

Linked notes

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