反応 #5440

反応方程式

H2O

Potassium t-butoxide

2-bromo-5-methoxyphenyl-propionate

diethyl oxalate

ether

ether

→

desired product

収率 90.0%

2-Oxo-3-carboethoxy-4-(2-bromo-5-methoxyphenyl)butanoic acid, ethyl ester

収率 90.0%

反応条件

後処理

1. 1
   その他the aqueous layer was separated
2. 2
   抽出extracted with ether
3. 3
   乾燥The ether layer was dried (MgSO4)
4. 4
   その他the solvent was evaporated

実験手順

Potassium t-butoxide (6.72 g) was suspended in 30 ml of anhydrous ether and cooled to 0° C. A solution of 14.35 g of ethyl 3-(2-bromo-5-methoxyphenyl-propionate and 10.95 g diethyl oxalate in 10 ml ether was added dropwise over 15 min. After 2 at 25° C., the reaction was poured into 100 ml H2O and the aqueous layer was separated, acidified to pH 1 and extracted with ether. The ether layer was dried (MgSO4) and the solvent was evaporated to yield 17.48 g of the desired product as a colorless oil (90%). NMR (CDCl3) δ1.20 (t, 3H), 1.35 (t, 3H), 3.32 (dd, 2H), 3.76 (s, 3H), 4.18 (q, 2H), 4.32 (q, 2H), 4.53 (t, 1H), 6.67 (dd, 1H), 6.80 (d, 1H), 7.40 (d, 1H).

出典