Reaktion #44618

Reaktionsgleichung

sodium hydroxide

water

toluene THF

(S)-1-[(S)-1-(2,6-difluoropyridin-3-yl)ethylamino]propan-2-ol (+)-di-p-toluoyl-D-tartrate

→

title compound

Ausbeute 115.4%

(S)-4-[(S)-1-(2,6-difluoropyridin-3-yl)ethyl]-6-methylmorpholin-2,3-dione

Ausbeute 115.4%

Lösungsmittel

toluene

Reaktionsbedingungen

Aufarbeitung

1. 1
   SonstigeThe organic layer was separated
2. 2
   ExtraktionThe water layer was extracted with 50% toluene-THF (800 mL) three times
3. 3
   Einengenconcentrated under reduced pressure
4. 4
   workup.ADDITIONTo the residue, diethyl oxalate (200 mL) was added
5. 5
   SonstigeThe resulting reaction solution
6. 6
   Temperaturwas heated to and
7. 7
   Temperaturcooled with ice
8. 8
   workup.STIRRINGwhile stirring
9. 9
   FiltrationThe precipitated crystal was filtered
10. 10
    Waschenwashed with toluene and diethyl ether
11. 11
    Sonstigedried in air

Vorschrift

A 5 N sodium hydroxide aqueous solution (450 mL), water (1000 mL), and 50% toluene-THF (2000 mL) were added to (S)-1-[(S)-1-(2,6-difluoropyridin-3-yl)ethylamino]propan-2-ol (+)-di-p-toluoyl-D-tartrate (199 g). The organic layer was separated. The water layer was extracted with 50% toluene-THF (800 mL) three times. All the organic layers were combined and concentrated under reduced pressure. To the residue, diethyl oxalate (200 mL) was added. The resulting reaction solution was heated to and stirred at 140 to 150° C. After 3 hr, the reaction solution was diluted with toluene (500 mL) and cooled with ice while stirring. The precipitated crystal was filtered, washed with toluene and diethyl ether, and dried in air to give 103 g of the title compound. The physical property values of this compound were as follows:

Quelle