Methanol → Methyl 5-oxo-5,6,7,8-tetrahydronaphthalene-2-carboxylate
Reaction equation
[O:1]=[C:2]1[CH2:11][CH2:10][CH2:9][C:8]2[CH:7]=[C:6]([C:12]([OH:14])=[O:13])[CH:5]=[CH:4][C:3]1=2.[CH3:15]O>Cl>[O:1]=[C:2]1[CH2:11][CH2:10][CH2:9][C:8]2[CH:7]=[C:6]([C:12]([O:14][CH3:15])=[O:13])[CH:5]=[CH:4][C:3]1=2Participants
Reactant 2
Product 1
Reagents, catalysts & solvents 1
Procedure
A solution of 5-oxo-5,6,7,8-tetrahydronaphthalene-2-carboxylic acid (5.14 g, 27.0 mmol) (Peakdale Molecular) in 4N hydrochloric acid in methanol was heated to reflux for eighteen hours. The solution was returned to ambient temperature and concentrated in vacuo. The residue was diluted with ethyl acetate and washed with saturated sodium bicarbonate solution and saturated sodium chloride and dried over magnesium sulfate. Filtration followed by concentration in vacuo provided methyl 5-oxo-5,6,7,8-tetrahydronaphthalene-2-carboxylate as a brown solid (4.76 g, 86% yield). Reversed-phase HPLC on 4.6×50 mm C-18 column, tR=1.90 minutes (10 to 90% acetonitrile/water over 4 minutes at 4 mL/minute with detection 254 nm, at 20° C.); 1H NMR (400 MHz, DMSO-d6) δ ppm 1.99-2.08 (m, 2H), 2.58-2.66 (m, 2H), 2.99 (t, J=6.04 Hz, 2H), 3.85 (s, 3H), 7.83-7.87 (m, 1H), 7.91 (d, J=0.81 Hz, 1H), 7.92-7.97 (m, 1H).
Workup
- temperatureto reflux for eighteen hours
- customwas returned to ambient temperature
- concentrationconcentrated in vacuo
- additionThe residue was diluted with ethyl acetate
- washwashed with saturated sodium bicarbonate solution and saturated sodium chloride
- dry with materialdried over magnesium sulfate
- filtrationFiltration
- concentrationfollowed by concentration in vacuo
Sources & evidence
- ORD record
- ord-9fac2d9edb0545da8095f7947b4aa171
- Source dataset
- uspto-grants-2010_08
- Patent number
- US07781428B2
Reaction notes
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