Nitric Acid → 4-Methoxy-1-nitro-dibenzofuran

HRID 641199Notes

Reaction equation

HRID 641199 reaction equation
[CH3:1][O:2][C:3]1[C:8]2[O:9][C:10]3[CH:15]=[CH:14][CH:13]=[CH:12][C:11]=3[C:7]=2[CH:6]=[CH:5][CH:4]=1.[N+:16]([O-])([OH:18])=[O:17].[OH-].[Na+].COC1C2OC3C=CC=CC=3C=2C=CC=1[N+]([O-])=O>C(O)(=O)C.O>[CH3:1][O:2][C:3]1[C:8]2[O:9][C:10]3[CH:15]=[CH:14][CH:13]=[CH:12][C:11]=3[C:7]=2[C:6]([N+:16]([O-:18])=[O:17])=[CH:5][CH:4]=1

Participants

7

Reactant 4

HCID 944Nitric AcidHCID 14798Sodium HydroxideHCID 119941974-MethoxydibenzofuranHCID 686898214-Methoxy-3-nitro-dibenzofuran

Product 1

HCID 498570844-Methoxy-1-nitro-dibenzofuranYield 48%

Reagents, catalysts & solvents 2

HCID 176Acetic AcidSolventHCID 962WaterSolvent

Procedure

To a solution of 4-methoxy-dibenzofuran (3.15 g; 15.89 mmol) in glacial acetic acid (50 mL), fuming nitric acid (2.6 mL; 63.50 mmol) was added dropwise. The reaction was kept at 20° C. during the addition and stirred for 3 h. Upon completion, the reaction mixture was poured carefully onto iced water; pH was adjusted to 7 by addition of 1 M sodium hydroxide, and the product was extracted in DCM. The organic layer was dried on magnesium sulfate, filtered and then concentrated. The residue was purified by flash chromatography using ethyl acetate/EP (1:19) as eluant. The first compound to come off the column was the 4-methoxy-3-nitro-dibenzofuran (270 mg, 1.11 mmol, 7%) then the title compound (1.85 g, 7.62 mmol, 48%) was obtained as a cream solid: Rf=0.13 (EtOAc-EP 1:19); mp: 155-156° C.; λmax (EtOH)/nm 239; IR (cm−1) 3092, 2917, 2851, 2042, 1876, 1630, 1568, 1506, 1438, 1396, 1342, 1297, 1274, 1239, 1205, 1159, 1129, 1091, 1002, 938, 888, 831, 812, 738, 676; 1H NMR, (300 MHz, CDCl3) δ 4.06 (3H, s, OCH3), 6.92 (1H, d, J=8 Hz), 7.18 (1H, t, J=8 Hz), 7.36 (2H, m), 8.17 (1H, d, J=8 Hz), 8.63 (1H, d, J=8 Hz); 13C NMR, (75 MHz, CDCl3) δ 56.81 (OCH3), 107.53, 111.81, 120.50 (Cq), 121.14 (Cq), 122.27, 123.71, 126.32, 129.55, 136.29 (Cq), 145.20 (Cq), 150.53 (Cq), 157.02 (Cq); MS (EI) m/z 243.1 M+; HRMS calcd for C13H9NO4 [M+H]+ 243.0526, found 243.0528.

Workup

  1. additionThe reaction was kept at 20° C. during the addition
  2. extractionthe product was extracted in DCM
  3. customThe organic layer was dried on magnesium sulfate
  4. filtrationfiltered
  5. concentrationconcentrated
  6. customThe residue was purified by flash chromatography

Sources & evidence

ORD record
ord-f389ebd4963043aea21c2c494c043eaa
Source dataset
uspto-grants-2010_04
Patent number
US07696203B2

Reaction notes

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