Borane;tetrahydrofuran → HCID 21102171, compound

HRID 2250287Notes

Reaction equation

HRID 2250287 reaction equation
[CH3:1][C:2]1[CH:3]=[C:4]([CH:8]=[C:9]([N+:14]([O-:16])=[O:15])[C:10]=1[N+:11]([O-:13])=[O:12])[C:5](O)=[O:6].B.O1CCCC1>O1CCCC1>[CH3:1][C:2]1[CH:3]=[C:4]([CH2:5][OH:6])[CH:8]=[C:9]([N+:14]([O-:16])=[O:15])[C:10]=1[N+:11]([O-:13])=[O:12]

Participants

4

Reactant 2

HCID 2723981Borane;tetrahydrofuran2×HCID 21102170HCID 21102170, compound

Product 1

HCID 21102171HCID 21102171, compoundYield 86%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent

Procedure

A solution of 3-methyl-4,5-dinitrobenzoic acid (4.0 g, 17.7 mmol) in tetrahydrofuran (200 mL) was cooled to −70° C. with a dry ice/acetone bath. To this solution was added borane-tetrahydrofuran (1M in tetrahydrofuran, 35.4 mL). The reaction mixture was allowed to slowly warm to room temperature and was stirred for 16 h. The reaction was incomplete, was again cooled to −50° C. and additional borane-tetrahydrofuran (1M in tetrahydrofuran, 35.4 mL) was added. Again, the reaction mixture was allowed to slowly warm to room temperature overnight. The reaction was quenched with a mixture of acetic acid and water (1:1, 30 mL) while cooling at 0° C. After stirring for 30 min, all organic solvent was evaporated and the aqueous material was neutralized by pouring into ice cold saturated sodium bicarbonate (350 mL) in small portions. The aqueous layer was extracted with ethyl acetate. The extracts were washed with brine, dried over magnesium sulfate, filtered and evaporated. The residue was subjected to flash column chromatography (1:2 hexanes/ethyl acetate) to give the title compound (3.2 g, 86% yield). 1H-NMR (CDCl3, 300 MHz) δ 8.00 (s, 1H), 7.62 (s, 1H), 4.82 (s, 2H), 2.41 (s, 3H). 13C-NMR (CDCl3, 75 MHz) δ 144.5, 143.3, 140.9, 134.3, 132.9, 120.8, 63.0, 17.4.

Workup

  1. temperaturewas again cooled to −50° C.
  2. temperatureto slowly warm to room temperature overnight
  3. customThe reaction was quenched with a mixture of acetic acid and water (1:1, 30 mL)
  4. temperaturewhile cooling at 0° C
  5. stirringAfter stirring for 30 min
  6. customall organic solvent was evaporated
  7. additionby pouring into ice cold saturated sodium bicarbonate (350 mL) in small portions
  8. extractionThe aqueous layer was extracted with ethyl acetate
  9. washThe extracts were washed with brine
  10. dry with materialdried over magnesium sulfate
  11. filtrationfiltered
  12. customevaporated

Sources & evidence

ORD record
ord-1f80ba8e7e654fd6af6b67c881096c86
Source dataset
uspto-grants-2008_01
Patent number
US07314883B2

Reaction notes

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