反应详情

41.8 g of hydrazine-N,N'-dicarboxylic acid di-tert-butyl ester, 74.5 g of potassium carbonate, 52.0 g of 2,2-dimethyl-1,3-propanediol dimethanesulfonate and 2.0 g of potassium iodide are stirred for 48 hours at 120°-130° C. in 360 ml of N,N-dimethylformamide. The reaction mixture is then concentrated; diethyl ether is added and the organic phase is washed with water. Mter drying over sodium sulfate, the reaction mixture is concentrated and purified by means of column chromatography to yield 1.1 g of the desired product, 4,4-dimethyl-pyrazolidine-N,N'-dicarboxylic acid di-tert-butyl ester, in the form of white crystals.

1. concentrationThe reaction mixture is then concentrated
2. additiondiethyl ether is added
3. washthe organic phase is washed with water
4. dry with materialMter drying over sodium sulfate
5. concentrationthe reaction mixture is concentrated
6. custompurified by means of column chromatography