Nitric Acid → 7-Nitro-1,2,3,4-tetrahydroquinoline

HRID 494170Notes

Reaction equation

HRID 494170 reaction equation
[NH:1]1[C:10]2[C:5](=[CH:6][CH:7]=[CH:8][CH:9]=2)[CH2:4][CH2:3][CH2:2]1.[N+:11]([O-])([OH:13])=[O:12].C(=O)([O-])[O-].[K+].[K+].CCOC(C)=O>S(=O)(=O)(O)O>[N+:11]([C:8]1[CH:9]=[C:10]2[C:5]([CH2:4][CH2:3][CH2:2][NH:1]2)=[CH:6][CH:7]=1)([O-:13])=[O:12]

Participants

6

Reactant 4

HCID 944Nitric AcidHCID 8857Ethyl AcetateHCID 11430Potassium CarbonateHCID 694601,2,3,4-Tetrahydroquinoline

Product 1

HCID 2525137-Nitro-1,2,3,4-tetrahydroquinoline

Reagents, catalysts & solvents 1

HCID 1118Sulfuric AcidSolvent2×

Conditions

Temperature
2.5 °C

Procedure

To a solution of 1,2,3,4-tetrahydroquinoline (6.5 g, 0.049 mol) in concentrated sulfuric acid (118 ml) cooled to 0° C. was added a solution of concentrated nitric acid (4.9 ml) in concentrated sulfuric acid (12 ml) dropwise over 0.3 h so as to maintain the temperature at 0-5° C. On completion of addition, the reaction mixture was poured onto crushed ice then neutralised with solid potassium carbonate. EtOAc (500 ml) was added and the mixture was filtered to remove undissolved solids then extracted with further EtOAc (4×500 ml). The combined extracts were dried over MgSO4 and concentrated in vacuo to give the crude product which was purified by flash column chromatography. Elution with 5% EtOAc/60-80° C. petroleum ether gave the title compound as an orange solid (5.46 g). 1H NMR (250 MHz, CDCl3) δ(ppm): 7.40 (dd, 1H), 7.26 (d, 1H), 7.02 (d, 1H), 4.16 (br, 1H), 3.35 (m, 2H), 2.81 (t, 2H), 1.95 (m, 2H).

Workup

  1. additionOn completion of addition
  2. additionthe reaction mixture was poured
  3. customonto crushed ice
  4. filtrationthe mixture was filtered
  5. customto remove undissolved solids
  6. extractionthen extracted with further EtOAc (4×500 ml)
  7. dry with materialThe combined extracts were dried over MgSO4
  8. concentrationconcentrated in vacuo
  9. customto give the crude product which
  10. customwas purified by flash column chromatography
  11. washElution with 5% EtOAc/60-80° C. petroleum ether

Sources & evidence

ORD record
ord-181e0e92367c47b2a6cde34954cb1e2d
Source dataset
uspto-grants-2009_05
Patent number
US07538121B2

Reaction notes

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