反応 #2383784

反応方程式

Phenylalanyl-β-alanine ethyl ester

ethyl bromoacetate

triethylamine

→

N-(carboethoxymethyl)phenylalanyl-β-alanine ethyl ester

収率 80.4%

溶媒

toluene

toluene

反応条件

後処理

1. 1
   workup.ADDITIONwas added dropwise over 0.5 hours
2. 2
   その他After completion of reaction
3. 3
   その他the resultant reaction mixture
4. 4
   抽出was subjected to extraction with ethyl acetate (20 g)
5. 5
   洗浄The organic layer was washed with a 2.5% aqueous solution of citric acid
6. 6
   その他Subsequently, the solvent was removed

実験手順

Phenylalanyl-β-alanine ethyl ester (10 g, 0.038 mol) and triethylamine (10.3 g, 0.1 mol) were suspended in toluene (45 g), and the suspension was heated to 60° C. To the resultant suspension, ethyl bromoacetate (9.3 g, 0.057 mol) suspended in toluene (5 g) was added dropwise over 0.5 hours, and then the resultant mixture was stirred for three hours. After completion of reaction, the resultant reaction mixture was subjected to extraction with ethyl acetate (20 g). The organic layer was washed with a 2.5% aqueous solution of citric acid. Subsequently, the solvent was removed, to thereby obtain N-(carboethoxymethyl)phenylalanyl-β-alanine ethyl ester (10.7 g, yield: 80.3%). The compound was dissolved in methanol, and a 48% aqueous solution of sodium hydroxide (6.6 g, 0.08 mol) was added to the methanol solution, and the resultant mixture was stirred for three hours. After completion of reaction, the solvent was removed, and the resultant residue was dissolved in water (20 mL), and then washed with ethyl acetate (10 g). Subsequently, hydrochloric acid was added to the aqueous layer, so as to attain a pH of 3.5. After being cooled, the resultant solution was subjected to filtration, to thereby obtain crude crystals. The crystals were recrystallized from a 20% aqueous solution of isopropyl alcohol, to thereby obtain compound 1 (6.0 g, yield: 67%).

出典