Réaction #586105

Équation de réaction

2-methyl-3-(trimethylsilyloxy)cyclopent-2-enone

ammonia

n-butyllithium

hydrochloric acid

8-bromoquinoline

→

2-methyl-3-(8-quinolyl)cyclopent-2-enone

Rendement 74.9%

Solvants

tetrahydrofuran

Conditions de réaction

Traitement

1. 1
   workup.STIRRINGThe mixture was stirred for a further 15 minutes
2. 2
   workup.STIRRINGwhile stirring
3. 3
   Températureto warm to room temperature
4. 4
   workup.STIRRINGwhile stirring
5. 5
   workup.STIRRINGwas stirred for a further one hour
6. 6
   Autrethe mixture obtained in this way
7. 7
   Températurewas refluxed for 3 hours
8. 8
   Températureto cool to room temperature
9. 9
   workup.STIRRINGwhile stirring
10. 10
    AutreThe aqueous phase was then separated off from the organic phase
11. 11
    Extractionthe aqueous phase was extracted twice with diethyl ether
12. 12
    Séchagedried over magnesium sulfate
13. 13
    Filtrationfiltered
14. 14
    workup.DISTILLATIONthe solvent was distilled off
15. 15
    AutreThe residue obtained in this way
16. 16
    workup.DISTILLATIONwas distilled at 119-139° C.

Mode opératoire

A mixture of 38.7 g (186 mmol) of 8-bromoquinoline in 250 ml of tetrahydrofuran was cooled to −80° C. and 74.4 ml of n-butyllithium (2.5 M in hexane, 186 mmol) were subsequently added while stirring. The mixture was stirred for a further 15 minutes and, while stirring, 49.9 g (186 mmol) of 2-methyl-3-(trimethylsilyloxy)cyclopent-2-enone were added. The mixture was allowed to warm to room temperature while stirring and was stirred for a further one hour. The reaction mixture was then hydrolyzed by means of a mixture of 40 g of ice and 30 ml of concentrated hydrochloric acid and the mixture obtained in this way was refluxed for 3 hours. The mixture was allowed to cool to room temperature while stirring and ammonia solution was added until the pH was 12. The aqueous phase was then separated off from the organic phase and the aqueous phase was extracted twice with diethyl ether. The organic phases were combined, dried over magnesium sulfate, filtered and the solvent was distilled off. The residue obtained in this way was distilled at 119-139° C. and 2×10−2 mbar to give 31.1 g (139.3 mmol, 74.9%) of 2-methyl-3-(8-quinolyl)cyclopent-2-enone.

Source