Реакция #64875

Уравнение реакции

tetrabutylammonium fluoride

hydrazine-N,N'-dicarboxylic acid di-tert-butyl ester

potassium carbonate

epibromohydrin

potassium iodide

→

4-hydroxy-pyrazolidine-N,N'-dicarboxylic acid di-tert-butyl ester

Растворители

ethyl methyl ketone

Условия реакции

Обработка

1. 1
   КонцентрированиеThe resulting suspension is concentrated
2. 2
   workup.ADDITION500 ml of diethyl ether are added
3. 3
   Фильтрацияthe reaction mixture is then filtered
4. 4
   Концентрированиеthe tiltrate is concentrated
5. 5
   ДругоеPurification of the crude product by means of column chromatography

Методика

46.4 g of hydrazine-N,N'-dicarboxylic acid di-tert-butyl ester, 69.0 g of potassium carbonate, 3.3 g of potassium iodide, 20 ml of tetrabutylammonium fluoride (1 molar solution in tetrahydrofuran) and 21 ml of epibromohydrin are boiled under reflux for 48 hours in 400 ml of ethyl methyl ketone. The resulting suspension is concentrated, and 500 ml of diethyl ether are added thereto; the reaction mixture is then filtered and the tiltrate is concentrated. Purification of the crude product by means of column chromatography yields 27.1 g of the desired 4-hydroxy-pyrazolidine-N,N'-dicarboxylic acid di-tert-butyl ester in the form of white crystals; m.p. 100°-102° C.

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