反応 #2286286

反応方程式

(3-chloro-4-hydroxy-5-methyl-phenyl)-acetic acid

(3-Chloro-4-hydroxy-5-methyl-phenyl)-acetic acid

sulfuric acid

methanol

→

acetic acid methyl ester

収率 91.0%

(3-Chloro-4-hydroxy-5-methyl-phenyl)-acetic acid methyl ester

収率 91.0%

反応条件

後処理

1. 1
   濃縮At this time, the reaction mixture was concentrated under vacuum
2. 2
   workup.ADDITIONThe resulting oil was diluted with ethyl acetate (100 mL)
3. 3
   洗浄The organics were washed with water (2×50 mL)
4. 4
   乾燥dried with magnesium sulfate
5. 5
   ろ過filtered
6. 6
   濃縮concentrated
7. 7
   その他The resulting residue was purified by column chromatography
8. 8
   洗浄eluted with 10% ethyl acetate in petroleum ether

実験手順

A solution of (3-chloro-4-hydroxy-5-methyl-phenyl)-acetic acid (5b) (1.4 g, 6.98 mmol) in methanol (60 mL) was treated with concentrated sulfuric acid (0.5 mL) at room temperature under argon. The reaction mixture was heated to 70° C. for 24 h. At this time, the reaction mixture was concentrated under vacuum. The resulting oil was diluted with ethyl acetate (100 mL). The organics were washed with water (2×50 mL), dried with magnesium sulfate, filtered and concentrated. The resulting residue was purified by column chromatography using silica gel eluted with 10% ethyl acetate in petroleum ether to afford 3-chloro-4-hydroxy-5-methyl-phenyl)-acetic acid methyl ester (6b) (1.36 g, 91%) as a white solid; EI(+)-HRMS m/z calcd for C10H11ClO3 (M+) 214.0397, found 214.0400. Molecular Weight=214.6504; Exact Mass=214.0397

出典