تفاعل #50945

معادلة التفاعل

HCl

4-methylenepyrazolidine-1,2-dicarboxylic acid 1-benzyl ester 2-tert-butyl ester

thionyl chloride

→

desired product

المردود 97.0%

4-methylene-pyrazolidine-1-carboxylic acid 1-benzyl ester

المردود 97.0%

المذيبات

methanol

ظروف التفاعل

المعالجة

1. 1
   أخرىConcentration of the reaction in vacuo
2. 2
   أخرىaffords a yellow oil which
3. 3
   أخرىcrystallizes

الإجراء التجريبي

To a solution of crude 4-methylenepyrazolidine-1,2-dicarboxylic acid 1-benzyl ester 2-tert-butyl ester, 8, (30 g) in methanol (300 ml.) is added thionyl chloride dropwise at 0° C. The reaction is warmed to room temperature and stirred an additional 18 hours. Concentration of the reaction in vacuo affords a yellow oil which crystallizes upon standing to provide 23 g (97% yield) of the desired product as the HCl salt.

المصدر