Methanol → Ethyl 2-methoxyquinoline-7-carboxylate
Reaction equation
[CH2:1]([O:3][C:4]([C:6]1[CH:15]=[C:14]2[C:9]([CH:10]=[CH:11][CH:12]=[N+:13]2[O-])=[CH:8][CH:7]=1)=[O:5])[CH3:2].C1(C)C=CC(S(Cl)(=O)=O)=CC=1.C(N(CC)CC)C.[CH3:35][OH:36]>>[CH3:35][O:36][C:12]1[CH:11]=[CH:10][C:9]2[C:14](=[CH:15][C:6]([C:4]([O:3][CH2:1][CH3:2])=[O:5])=[CH:7][CH:8]=2)[N:13]=1Participants
Procedure
To a 0° C. solution of 7-(ethoxycarbonyl)quinoline 1-oxide (150 mg, 0.69 mmol) and toluene-4-sulphonyl chloride (171 mg, 0.89 mmol) in methanol (5 mL) was added triethylamine (0.19 mL, 1.4 mmol). The reaction was stirred at room temperature overnight. LCMS showed the reaction was incomplete. Additional triethylamine (0.05 mL) was added and the reaction was stirred for another 4 hours. The reaction was concentrated and the residue partitioned between ethyl acetate and saturated aqueous sodium carbonate. The layers were separated and the aqueous was extracted two more times with ethyl acetate. The combined organics were washed with brine, dried over sodium sulfate, filtered, and concentrated. Purification by flash column chromatography (0-40% ethyl acetate/heptanes) gave the title compound (130 mg, 81%) as a pale yellow solid. +ESI (M+H) 232.2; 1H NMR (400 MHz, CDCl3, δ): 8.49-8.60 (m, 1H), 7.95-8.05 (m, 2H), 7.75 (d, J=8.19 Hz, 1H), 6.98 (d, J=8.78 Hz, 1H), 4.43 (q, J=7.22 Hz, 2H), 4.08 (s, 3H), 1.43 (t, J=7.12 Hz, 3H).
Workup
- stirringthe reaction was stirred for another 4 hours
- concentrationThe reaction was concentrated
- customthe residue partitioned between ethyl acetate and saturated aqueous sodium carbonate
- customThe layers were separated
- extractionthe aqueous was extracted two more times with ethyl acetate
- washThe combined organics were washed with brine
- dry with materialdried over sodium sulfate
- filtrationfiltered
- concentrationconcentrated
- customPurification by flash column chromatography (0-40% ethyl acetate/heptanes)
Sources & evidence
- ORD record
- ord-2041ce008c7c44cb8a8a2748d466c516
- Source dataset
- uspto-grants-2014_10
- Patent number
- US08859773B2
Reaction notes
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