Magnesium Chloride → Ethyl 5,6-dihydro-4H-pyrrolo[3,2,1-ij]quinoline-1-carboxylate

HRID 557159

Reaction equation

HRID 557159 reaction equation
[Cl-].[Mg+2].[Cl-].[CH2:4]([O:6][C:7](=[O:21])[C:8](=O)[CH2:9][N:10]1[C:19]2[C:14](=[CH:15][CH:16]=[CH:17][CH:18]=2)[CH2:13][CH2:12][CH2:11]1)[CH3:5]>COCCO.O1CCCC1>[CH2:4]([O:6][C:7]([C:8]1[C:18]2=[C:19]3[C:14](=[CH:15][CH:16]=[CH:17]2)[CH2:13][CH2:12][CH2:11][N:10]3[CH:9]=1)=[O:21])[CH3:5]

Participants

5

Reactant 2

HCID 5360315Magnesium Chloride2×HCID 20729419ethyl 3-(3,4-dihydroquinolin-1(2H)-yl)-2-oxopropanoate

Product 1

HCID 20729414Ethyl 5,6-dihydro-4H-pyrrolo[3,2,1-ij]quinoline-1-carboxylateYield 48%

Reagents, catalysts & solvents 2

HCID 80192-MethoxyethanolSolvent2×HCID 8028TetrahydrofuranSolvent

Procedure

Add magnesium chloride (27.7 g, 0.29 mol) to 2-methoxyethanol (400 mL) and heat the mixture to reflux. Add a solution of 3-(3,4-Dihydro-2H-quinolin-1-yl)-2-oxopropionic acid ethyl ester (0.29 mol) in 2-methoxyethanol (100 mL) and tetrahydrofuran (40 mL) slowly to the MgCl2 mixture over 1 hour. Upon completion of addition, stir the mixture for 5 hours at reflux, and then concentrate under reduced pressure. Treat the concentrated crude mixture with 2N hydrochloric acid (500 mL) and extract with dichloromethane (3×400 mL). Combine the organic layers, dry over sodium sulfate, filter, and concentrate under reduced pressure. Subject the residue to silica gel chromatography, eluting with 20% ethyl acetate/hexanes. Combine fractions containing product and concentrate them under reduced pressure to provide the desired compound as an orange solid (31.6 g, 48%).

Workup

  1. temperatureheat the mixture
  2. temperatureto reflux
  3. additionUpon completion of addition
  4. temperatureat reflux
  5. concentrationconcentrate under reduced pressure
  6. additionTreat the
  7. concentrationconcentrated crude mixture with 2N hydrochloric acid (500 mL)
  8. extractionextract with dichloromethane (3×400 mL)
  9. dry with materialCombine the organic layers, dry over sodium sulfate
  10. filtrationfilter
  11. concentrationconcentrate under reduced pressure
  12. washeluting with 20% ethyl acetate/hexanes
  13. additionCombine fractions containing product
  14. concentrationconcentrate them under reduced pressure

Sources & evidence

ORD record
ord-027815fc8a4346e6a8aebd9870d33e5a
Source dataset
uspto-grants-2011_11
Patent number
US08058425B2

Linked notes

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