Reaktion #5689

Reaktionsgleichung

indole

4-chlorobenzyl chloride

KOH

→

1-(4-chlorobenzyl)indole

Ausbeute 84.1%

Lösungsmittel

H2O

toluene

H2O

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturheated at 55°-65° for 22 hours
2. 2
   SonstigeThe layers were separated
3. 3
   ExtraktionThe aqueous layer was extracted with 100 mL of toluene
4. 4
   WaschenThe combined organic phases were washed with 2N HCl (2×50 mL), H2O (2×50 mL), and 50 mL of brine
5. 5
   Trocknendried over MgSO4
6. 6
   SonstigeEvaporation of the solvent
7. 7
   workup.WAITleft 29 g of orange-brown oil
8. 8
   SonstigeThe oil was chromatographed on a 1100 g column of silica gel
9. 9
   WaschenThe column was eluted with 1:1 CH2Cl2 -Skellysolve B and 200 mL fractions
10. 10
    Sonstigewere collected
11. 11
    SonstigeFractions 12-19 were combined giving 23.11 g of crude product as a pink oil The oil
12. 12
    Sonstigewas chromatographed on a 1100 g column of silica gel
13. 13
    WaschenThe column was eluted with 25% CH2Cl2 -Skellysolve B and 200 mL fractions
14. 14
    Sonstigewere collected

Vorschrift

A mixture of 11.72 g (0.1 mole) of indole, 17.71 g (0.11 mole) of 4-chlorobenzyl chloride, 33 g (0.5 mole) of 85% KOH, 14 mL of H2O, 2.5 g (2.5 mmoles) of PEG-1000 and 100 mL of toluene was stirred and heated at 55°-65° for 22 hours. After cooling to room temperature, 50 mL of H2O was added. The layers were separated. The aqueous layer was extracted with 100 mL of toluene. The combined organic phases were washed with 2N HCl (2×50 mL), H2O (2×50 mL), and 50 mL of brine and dried over MgSO4. Evaporation of the solvent left 29 g of orange-brown oil. The oil was chromatographed on a 1100 g column of silica gel. The column was eluted with 1:1 CH2Cl2 -Skellysolve B and 200 mL fractions were collected. The fractions were assayed by silica gel tlc (1×4") (25% CH2Cl2 -Skellysolve B). Fractions 12-19 were combined giving 23.11 g of crude product as a pink oil The oil was chromatographed on a 1100 g column of silica gel. The column was eluted with 25% CH2Cl2 -Skellysolve B and 200 mL fractions were collected. The fractions were assayed as before. Fractions 20-30 were combined giving 20.33 g (84%) of 1-(4-chlorobenzyl)indole as a yellow oil.

Quelle