Reaktion #1359292

Reaktionsgleichung

potassium carbonate

water

1-(2-tert-butoxycarbonylamino-1-methyl-ethyl)-6-chloro-5-methyl-1H-pyrrolo[2,3-b]pyridine-2-carboxylic acid ethyl ester

trifluoroacetic acid

→

product

Ausbeute 73.7%

6-Chloro-4,7-dimethyl-3,4-dihydro-2H-2,4a,5-triaza-fluoren-1-one

Ausbeute 73.7%

Lösungsmittel

ethyl acetate

dichloromethane

Reaktionsbedingungen

Aufarbeitung

1. 1
   Sonstigethe ice-bath was removed
2. 2
   workup.ADDITIONafter complete addition
3. 3
   Sonstigethe volatile components were removed
4. 4
   workup.DISSOLUTIONthe residue was dissolved in 3 mL methanol
5. 5
   Extraktionthe separated aqueous phase was extracted twice with ethyl acetate
6. 6
   WaschenThe combined organic layers were washed with brine
7. 7
   Trocknendried over magnesium sulfate
8. 8
   Sonstigeevaporated
9. 9
   workup.DISSOLUTIONThe residue was dissolved in dichloromethane
10. 10
    Sonstigetert-butyl methyl ether, evaporated under vacuum until a suspension
11. 11
    FiltrationThe ice-cold suspension was filtered
12. 12
    Waschenthe filter cake was washed with tert-butyl methyl ether

Vorschrift

To an ice-cold solution of 0.50 g (1.25 mmol) ®-1-(2-tert-butoxycarbonylamino-1-methyl-ethyl)-6-chloro-5-methyl-1H-pyrrolo[2,3-b]pyridine-2-carboxylic acid ethyl ester in 6 mL dichloromethane was added 1.91 mL (2.85 g, 25.0 mmol) trifluoroacetic acid; the ice-bath was removed after complete addition. After 45 min., the volatile components were removed and the residue was dissolved in 3 mL methanol then treated cautiously with 0.70 g (5.0 mmol) potassium carbonate. After 2 h the reaction mixture was poured into water and ethyl acetate and the separated aqueous phase was extracted twice with ethyl acetate. The combined organic layers were washed with brine, dried over magnesium sulfate and evaporated. The residue was dissolved in dichloromethane and tert-butyl methyl ether, evaporated under vacuum until a suspension appeared, then cooled to 0° C. The ice-cold suspension was filtered and the filter cake was washed with tert-butyl methyl ether to give the product as a colourless solid (73.7%).

Quelle