反応 #82447

反応方程式

lithium hydroxide

ethyl trans-4-methyl-2,4-pentadienecarboxylate

→

trans-4-methyl-2,4-pentadienecarboxylic acid

収率 76.0%

溶媒

water

methanol

tetrahydrofuran

water

反応条件

後処理

1. 1
   抽出is extracted once using diethyl ether
2. 2
   その他is established in the aqueous phase at 0° C.
3. 3
   抽出The mixture is extracted
4. 4
   洗浄the combined organic phases are washed several times with water and saturated sodium chloride solution
5. 5
   その他after drying
6. 6
   濃縮concentrating

実験手順

2.5 g (0.1 mol) of lithium hydroxide are added at 0° C. to 10 g (0.07 mol) of ethyl trans-4-methyl-2,4-pentadienecarboxylate, dissolved in a solvent mixture of 75 ml of methanol, 17 ml of tetrahydrofuran and 2.5 ml of water, and the mixture is stirred for 20 hours at room temperature. After the mixture has been diluted with 200 ml of water, it is extracted once using diethyl ether, and a pH of 1 is established in the aqueous phase at 0° C. using concentrated hydrochloric acid. The mixture is extracted using diethyl ether, the combined organic phases are washed several times with water and saturated sodium chloride solution, and, after drying and concentrating, 6.1 g (76% of theory) of trans-4-methyl-2,4-pentadienecarboxylic acid are obtained. ##STR208##

出典