Réaction #4881

Équation de réaction

diisopropyl amine

n-butyllithium

hexane

2-chloroquinoline

dry ice

→

white crystals

Rendement 62.0%

2-Chloro-3-quinolinecarboxylic acid

Rendement 62.0%

Solvants

tetrahydrofuran

tetrahydrofuran

Conditions de réaction

Traitement

1. 1
   Températurewhile maintaining the temperature at -60° to -70° C
2. 2
   workup.ADDITIONSubsequent to this addition
3. 3
   Températurewhile maintaining the temperature at -60° to -70° C
4. 4
   Autreat -65° C.
5. 5
   Autrefor 20 minutes
6. 6
   workup.ADDITIONsubsequent to this addition
7. 7
   Autrethe entire reaction mixture
8. 8
   AutreMost of the solvent was evaporated in a stream of air
9. 9
   Autrethe residual solvent was removed by rotary evaporation
10. 10
    Lavagewashed with 3×50 ml of isopropyl ether
11. 11
    FiltrationThe aqueous layer was filtered
12. 12
    AutreThe precipitate was collected
13. 13
    Lavagewashed with water, isopropyl alcohol, and isopropyl ether
14. 14
    Autredried

Mode opératoire

To a solution of 21.3 ml (0.15 mole) of diisopropyl amine in 300 ml of dry tetrahydrofuran under a continuous nitrogen blanket, at -70° C., was added 61.6 ml of 2.7M n-butyllithium in hexane (0.165 mole) while maintaining the temperature at -60° to -70° C. Subsequent to this addition, the temperature was maintained at -65° C. for approximately 20 minutes. A solution of 20 g (0.12 mole) of 2-chloroquinoline in 60 ml of tetrahydrofuran was added dropwise while maintaining the temperature at -60° to -70° C. After holding the temperature at -65° C. for 20 minutes subsequent to this addition, the entire reaction mixture was poured onto a large excess of dry ice. Most of the solvent was evaporated in a stream of air; the residual solvent was removed by rotary evaporation. The residue was taken up in 300 ml water, made basic with dil aq. sodium hydroxide and washed with 3×50 ml of isopropyl ether. The aqueous layer was filtered and made acidic (4 to 5 pH) with dilute aqueous hydrochloric acid. The precipitate was collected, washed with water, isopropyl alcohol, and isopropyl ether, and dried, giving 15.4 g (62%) of white crystals, m.p. 190°-210° C. (decomp.). A sample was recrystallized from isopropyl alcohol giving an analytical sample, m.p. 190°-210° C. (decomp.).

Source