تفاعل #657229

معادلة التفاعل

2-(1-bromoethyl)-2-(6-methoxy-2-naphthyl)-1,3-dioxolane-4(R),5(R)-dicarboxylic acid diethyl ester

sodium hydroxide

dimethoxyethane

→

2-(1-bromoethyl)-2-(6-methoxy-2-naphthyl)-1,3-dioxolane-4(R),5(R)-dicarboxylic acid

المردود 85.5%

المذيبات

water

water

ظروف التفاعل

المعالجة

1. 1
   أخرىprepared in a similar manner
2. 2
   استخلاصextracted with diethylether
3. 3
   استخلاصextracted with diethylether
4. 4
   غسيلThe organic phase was washed with water
5. 5
   تجفيفdried over sodium sulphate
6. 6
   أخرىEvaporation of the solvent under reduced pressure

الإجراء التجريبي

A mixture of the two diastereoisomers of 2-(1-bromoethyl)-2-(6-methoxy-2-naphthyl)-1,3-dioxolane-4(R),5(R)-dicarboxylic acid diethyl ester 3 and 4 (prepared in a similar manner as described in the example 1) (21.18 g, 0.044 mol, ratio 3:4=1:1), sodium hydroxide (3.52 g, 0.088 mol), dimethoxyethane (35 ml) and of water (35 ml) was kept, under stirring, at room temperature for 2 hours. The reaction mixture was diluted with water and extracted with diethylether. The aqueous phase was acidified with concentrated hydrochloric acid to pH 1 and extracted with diethylether. The organic phase was washed with water and dried over sodium sulphate. Evaporation of the solvent under reduced pressure gave the two diastereoisomers of 2-(1-bromoethyl)-2-(6-methoxy-2-naphthyl)-1,3-dioxolane-4(R),5(R)-dicarboxylic acid 5 and 6 (16 g, 0.0367 mol; yield 85.5%) in ratio 5:6=1:1 (determined by 1H-NMR 200 MHz).

المصدر