Réaction #320676

Équation de réaction

sodium carbonate

N-Chlorosuccinimide

(2β,3α,5α)-3-hydroxy-20-[(2-hydroxyethyl)imino]-2-(2,2-dimethyl-4-morpholinyl)pregnan-11-one

hydrochloric acid

→

(2β,3α,5α)-21-chloro-3-hydroxy-2-(2,2-dimethyl-4-morpholinyl)pregnane-11,20-dione

Solvants

tetrahydrofuran

water

Conditions de réaction

Traitement

1. 1
   workup.STIRRINGAfter stirring at room temperature for 1.25 h
2. 2
   Filtrationthe precipitated solid was filtered off
3. 3
   Lavagewashed with water
4. 4
   workup.DISSOLUTIONdissolved in dichloromethane
5. 5
   SéchageAfter drying over sodium sulfate
6. 6
   Autrethe solvent was removed under reduced pressure
7. 7
   Autrethe residue was chromatographed on silica gel
8. 8
   AutreThe purified product was crystallised from diethyl ether

Mode opératoire

N-Chlorosuccinimide (2.16 g) was added to a solution of (2β,3α,5α)-3-hydroxy-20-[(2-hydroxyethyl)imino]-2-(2,2-dimethyl-4-morpholinyl)pregnan-11-one (8.77 g) in tetrahydrofuran (175 ml). The solution was stirred at room temperature for 2 h and hydrochloric acid (53 ml; 1M) was then added. After stirring at room temperature for 1.25 h, the reaction mixture was poured into water (1 l). The pH was adjusted to 9 with aqueous sodium carbonate and the precipitated solid was filtered off, washed with water and dissolved in dichloromethane. After drying over sodium sulfate, the solvent was removed under reduced pressure and the residue was chromatographed on silica gel. The purified product was crystallised from diethyl ether to give (2β,3α,5α)-21-chloro-3-hydroxy-2-(2,2-dimethyl-4-morpholinyl)pregnane-11,20-dione (3.23 g). m.p. 206°-208° C. (dec); [α]D +130.5° (c 0.57).

Source