反応 #432406

反応方程式

Sulfuric acid

water

2,4,6-Trimethylbenzoic acid

Sodium hydroxide

sodium bisulfite

potassium permanganate

→

product

収率 89.0%

2,6-Dimethyl-terephthalic Acid

収率 89.0%

反応条件

後処理

1. 1
   workup.ADDITIONwere gradually added
2. 2
   温度heated on a steam bath for 15-30 minutes
3. 3
   workup.ADDITIONgradually added at 0° C
4. 4
   ろ過The precipitated white solid was filtered
5. 5
   workup.DISSOLUTIONdissolved in 5 N ammonium hydroxide
6. 6
   洗浄The solution was washed with diethyl ether
7. 7
   workup.ADDITIONgradually treated dropwise with concentrated sulfuric acid
8. 8
   その他to precipitate the product
9. 9
   ろ過Filtration
10. 10
    洗浄by washing with hot water (4×) and petroleum ether (3×), recrystallization (methanol-water)
11. 11
    その他drying at high vacuum

実験手順

2,4,6-Trimethylbenzoic acid (mesitoic acid) (10 g, 61 mmol) was suspended in 150 mL of water, and the mixture cooled to 0° C. Sodium hydroxide pellets (7.31 g, 0.18 mol) were gradually added, followed by addition of potassium permanganate (4×7.2 g, 0.18 mol) at four intervals of 30 minutes. The mixture was stirred at room temperature for 2 hours, then heated on a steam bath for 15-30 minutes. Sulfuric acid (200 mL, 9 mol) was added, then sodium bisulfite was carefully and gradually added at 0° C. The precipitated white solid was filtered and then dissolved in 5 N ammonium hydroxide. The solution was washed with diethyl ether, then gradually treated dropwise with concentrated sulfuric acid to precipitate the product. Filtration, followed by washing with hot water (4×) and petroleum ether (3×), recrystallization (methanol-water), and drying at high vacuum gave 10.5 g (89%) of the product as a white solid, m.p. >300° C. (ref. W. A. Noyes, Amer. Chem. J., 20, 789 (1898)).

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