Bromide ion → HCID 57522509, compound

HRID 1041182Notes

Reaction equation

HRID 1041182 reaction equation
[Br:1][C:2]1[C:7]2[CH2:8][CH2:9][C:10](=[O:13])[CH2:11][CH2:12][C:6]=2[C:5]([O:14][CH3:15])=[CH:4][CH:3]=1.S(=O)(=O)(O)O.[N+:21]([O-])([O-:23])=[O:22].[K+].[Br-]>C(Cl)Cl>[Br:1][C:2]1[C:7]2[CH2:8][CH2:9][C:10](=[O:13])[CH2:11][CH2:12][C:6]=2[C:5]([O:14][CH3:15])=[C:4]([N+:21]([O-:23])=[O:22])[CH:3]=1

Participants

6

Reactant 4

HCID 259Bromide ionHCID 1118Sulfuric AcidHCID 24434Potassium Nitrate2×HCID 57522508HCID 57522508, compound

Product 1

HCID 57522509HCID 57522509, compoundYield 77.1%

Reagents, catalysts & solvents 1

HCID 6344DichloromethaneSolvent

Procedure

To a stirred solution of 1-bromo-4-methoxy-5,6,8,9-tetrahydro-benzocyclohepten-7-one (20.0 g, 0.0743 mol) in sulfuric acid (200 mL, 4 mol) at 0° C. under an atmosphere of nitrogen was added potassium nitrate (7.89 g, 0.0780 mol) in portions. Note: When excess potassium nitrate is added, ipso substitution of the bromide is observed. After stirring for ˜15 min., an aliquot was removed and analyzed by HPLC indicating the completion of the reaction. Mixture was poured over ice water. A gummy solid formed which was dissolved in methylene chloride. The reaction mixture was transferred to a separatory funnel and the water layer removed. The organic phase was washed with saturated aqueous bicarbonate and water, dried over magnesium sulfate, filtered and concentrated in vacuo to an orange solid. Product was purified by ISCO chromatography on silica gel (350 g column) using ethyl acetate-hexane (10-100%). Fractions corresponding to product were combined and concentrated in vacuo to give 4-Bromo-1-Methoxy-2-nitro-5,6,8,9-tetrahydrobenzocyclohepten-7-one (18 g, 77%) as an orange solid. 1H NMR (CDCl3, 400 MHz) 8.04 (s, 1H), 3.90 (s, 3H), 3.25 (m, 2H), 3.15 (m, 2H), 2.64 (m, 4H).

Workup

  1. customan aliquot was removed
  2. customthe completion of the reaction
  3. customA gummy solid formed which
  4. customThe reaction mixture was transferred to a separatory funnel
  5. customthe water layer removed
  6. washThe organic phase was washed with saturated aqueous bicarbonate and water
  7. dry with materialdried over magnesium sulfate
  8. filtrationfiltered
  9. concentrationconcentrated in vacuo to an orange solid
  10. customProduct was purified by ISCO chromatography on silica gel (350 g column)
  11. concentrationconcentrated in vacuo

Sources & evidence

ORD record
ord-89644cc3bb4a4c7cbdc3cef08b3b9a5d
Source dataset
uspto-grants-2013_10
Patent number
US08552186B2

Reaction notes

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