Oxalyl chloride → methyl 2-(5,6-dihydro-4H-pyrrolo[3,2,1-ij]quinolin-1-yl)-2-oxoacetate
Reaction equation
[C:1](Cl)(=[O:5])[C:2](Cl)=[O:3].[CH:7]1[C:17]2=[C:18]3[C:13](=[CH:14][CH:15]=[CH:16]2)[CH2:12][CH2:11][CH2:10][N:9]3[CH:8]=1.[CH3:19][O-:20].[Na+]>C(OCC)C.C(OCC)(=O)C>[CH3:19][O:20][C:1](=[O:5])[C:2]([C:7]1[C:17]2=[C:18]3[C:13](=[CH:14][CH:15]=[CH:16]2)[CH2:12][CH2:11][CH2:10][N:9]3[CH:8]=1)=[O:3]Participants
Reactant 3
Product 1
Reagents, catalysts & solvents 2
Conditions
- Temperature
- 0 °C
Procedure
Add oxalyl chloride (1.05 mL, 12.08 mmol) dropwise to a solution of 5,6dihydro-4H-pyrolo[3,2,1-ij]quinoline (1.67 g, 10.6 mmol) in 150 mL of anhydrous diethyl ether at 0° C. and stir the resulting solution at 0° C. for 40 minutes. Cool the mixture to −78° C. and slowly add sodium methoxide (42 mL, 21 mmol, 0.5 M in methanol). Upon completion of the addition, remove the dry ice bath and allow the reaction to warm to 20-24° C. over 2 hours. Dilute the mixture with ethyl acetate (200 mL), wash with water (100 mL) and separate the layers. Wash the organic layer with saturated aqueous sodium chloride (50 mL), dry over sodium sulfate, filter, and concentrate under reduced pressure. Dissolve the residue in ethyl acetate (100 mL), filter through a 2 inch plug of coarse silica gel, and concentrate under reduced pressure to give the title compound as a yellow solid (2.16 g, 84%).
Workup
- temperatureCool the mixture to −78° C.
- additionUpon completion of the addition
- customremove the dry ice bath
- customthe reaction
- temperatureto warm to 20-24° C. over 2 hours
- washwash with water (100 mL)
- customseparate the layers
- washWash the organic layer with saturated aqueous sodium chloride (50 mL)
- dry with materialdry over sodium sulfate
- filtrationfilter
- concentrationconcentrate under reduced pressure
- dissolutionDissolve the residue in ethyl acetate (100 mL)
- filtrationfilter through a 2 inch plug of coarse silica gel
- concentrationconcentrate under reduced pressure
Sources & evidence
- ORD record
- ord-0ac53626c13843d8b37aeb6902406d8d
- Source dataset
- uspto-grants-2009_02
- Patent number
- US07491716B2
Reaction notes
Loading…