反応 #740383

反応方程式

2,5-dimethoxy-3,4,6-trimethylbenzaldehyde

sodium pyruvate

potassium hydroxide

→

4-(2',5'-dimethoxy-3',4',6'-trimethylphenyl)-2-keto-3-butenoic acid

収率 100.0%

溶媒

methanol

反応条件

後処理

1. 1
   温度the mixture is subsequently heated
2. 2
   温度at reflux for 5 hours
3. 3
   その他whereby a yellow solution is obtained
4. 4
   その他the resulting 4-(2',5'-dimethoxy-3',4',6'-trimethylphenyl)-2-keto-3-butenoic acid is precipitated by the addition of sulphuric acid
5. 5
   workup.STIRRINGThe suspension is stirred for 1 hour
6. 6
   ろ過filtered
7. 7
   洗浄the filter residue is washed with water
8. 8
   その他dried

実験手順

A suspension of 3.7 g (17.6 mmol) of 2,5-dimethoxy-3,4,6-trimethylbenzaldehyde and 5.0 g (53.2 mmol) of sodium pyruvate in 20 ml of methanol is treated with 0.1 g (1.8 mmol) of potassium hydroxide and the mixture is subsequently heated at reflux for 5 hours, whereby a yellow solution is obtained. The reaction mixture is poured on to ice-water and the resulting 4-(2',5'-dimethoxy-3',4',6'-trimethylphenyl)-2-keto-3-butenoic acid is precipitated by the addition of sulphuric acid while stirring. The suspension is stirred for 1 hour, filtered, the filter residue is washed with water and dried. In this manner there are obtained 4.9 g of 4-(2',5'-dimethoxy-3',4',6'-trimethylphenyl)-2-keto-3-butenoic acid in the form of a yellow powder of melting point 126°-127° C.

出典