تفاعل #93995

معادلة التفاعل

4-Methoxycarbonyl-2-methylbutanoic acid

L-proline tert.-butyl ester

dicyclohexylcarbodiimide

→

1-(4-methoxycarbonyl-2-methylbutanoyl)-L-proline tert.-butyl ester

المذيبات

dichloromethane

ظروف التفاعل

المعالجة

1. 1
   درجة الحرارةThe solution is chilled
2. 2
   ترشيحthe precipitate is filtered off
3. 3
   تركيزthe filtrate is concentrated to dryness in vacuo
4. 4
   أخرىThe residue is chromatographed on a column of silica gel with chloroform

الإجراء التجريبي

4-Methoxycarbonyl-2-methylbutanoic acid (3.1 g.) and L-proline tert.-butyl ester (3.78 g.) are dissolved in dichloromethane (40 ml.). The solution is chilled with stirring in an ice bath and dicyclohexylcarbodiimide (4.12 g.) is added. After stirring 15 minutes in the ice bath and 18 hours at room temperature, the precipitate is filtered off and the filtrate is concentrated to dryness in vacuo. The residue is chromatographed on a column of silica gel with chloroform to obtain 1-(4-methoxycarbonyl-2-methylbutanoyl)-L-proline tert.-butyl ester, yield 3.5 g.

المصدر