Acetic Acid → 2,2,4,5,6-Pentamethyl-7-nitro-2,3-dihydrobenzofuran

HRID 234272Notes

Reaction equation

HRID 234272 reaction equation
C(O)(=O)C.[N+:5]([O-:8])(O)=[O:6].[CH3:9][C:10]1([CH3:22])[CH2:14][C:13]2[C:15]([CH3:21])=[C:16]([CH3:20])[C:17]([CH3:19])=[CH:18][C:12]=2[O:11]1>C(OC(=O)C)(=O)C>[CH3:9][C:10]1([CH3:22])[CH2:14][C:13]2[C:15]([CH3:21])=[C:16]([CH3:20])[C:17]([CH3:19])=[C:18]([N+:5]([O-:8])=[O:6])[C:12]=2[O:11]1

Participants

5

Reactant 3

HCID 176Acetic AcidHCID 944Nitric AcidHCID 190785652,2,4,5,6-Pentamethyl-2,3-dihydrobenzofuran

Product 1

HCID 190785692,2,4,5,6-Pentamethyl-7-nitro-2,3-dihydrobenzofuranYield 9.8%

Reagents, catalysts & solvents 1

HCID 7918Acetic AnhydrideSolvent2×

Procedure

The mixed solution of acetic anhydride (5 ml) and acetic acid (5 ml) was cooled and nitric acid (5 ml) was added cautiously with stirring. Then, a solution of 2,2,4,5,6-pentamethyl-2,3-dihydrobenzofuran (2.9 g, 13.9 mmol) in acetic anhydride (5 ml) was added dropwise and the mixture was stirred for 30 minutes. The reaction mixture was poured into ice-cold water and the product was extracted with ethyl acetate. The extract was washed with saturated sodium bicarbonate solution, dried and concentrated. The residue was purified by column chromatography on silica gel (hexane-isopropyl ether, 9:1) and crystallized from methanol to obtain the desired compound (0.35 g, yield: 9.8% yield), m.p. 100°-101° C.

Workup

  1. stirringthe mixture was stirred for 30 minutes
  2. additionThe reaction mixture was poured into ice-cold water
  3. extractionthe product was extracted with ethyl acetate
  4. washThe extract was washed with saturated sodium bicarbonate solution
  5. customdried
  6. concentrationconcentrated
  7. customThe residue was purified by column chromatography on silica gel (hexane-isopropyl ether, 9:1)
  8. customcrystallized from methanol

Sources & evidence

ORD record
ord-76fa3ab2770649baa1ab9b49cf99eb2a
Source dataset
uspto-grants-1997_01
Patent number
US05594154

Reaction notes

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