反応 #64875

ord-da71adb801284935aabd431835879a32

反応条件

詳細条件
See reaction.notes.procedure_details.

後処理

  1. 1
    濃縮The resulting suspension is concentrated
  2. 2
    workup.ADDITION500 ml of diethyl ether are added
  3. 3
    ろ過the reaction mixture is then filtered
  4. 4
    濃縮the tiltrate is concentrated
  5. 5
    その他Purification of the crude product by means of column chromatography

実験手順

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.

出典

DOI: 10.6084/m9.figshare.5104873.v1特許: US05416065uspto-grants-1995_05