Benzyl Bromide → 1-Benzyl-5-chloro-1H-indole

HRID 5596

Reaction equation

HRID 5596 reaction equation
C1OCCOCCOCCOCCOCCOC1.CC(C)([O-])C.[K+].[Cl:25][C:26]1[CH:27]=[C:28]2[C:32](=[CH:33][CH:34]=1)[NH:31][CH:30]=[CH:29]2.[CH2:35](Br)[C:36]1[CH:41]=[CH:40][CH:39]=[CH:38][CH:37]=1>CCOCC.O>[CH2:35]([N:31]1[C:32]2[C:28](=[CH:27][C:26]([Cl:25])=[CH:34][CH:33]=2)[CH:29]=[CH:30]1)[C:36]1[CH:41]=[CH:40][CH:39]=[CH:38][CH:37]=1

Participants

7

Reactant 4

HCID 7498Benzyl BromideHCID 2855718-Crown-6HCID 871105-ChloroindoleHCID 23665647Potassium tert-butoxide

Product 1

HCID 184763621-Benzyl-5-chloro-1H-indoleYield 90%

Reagents, catalysts & solvents 2

HCID 962WaterSolventHCID 3283Diethyl EtherSolvent2×

Procedure

To a solution of 0.8 g (3.03 mmoles) of 18-crown-6 in 100 mL of dry ether was added 4.39 g (39.12 mmoles) potassium tert-butoxide. The mixture was stirred while 5.08 g (33.51 mmoles) of 5-chloroindole was added. The stirring was continued for 0.5 hour. Most of the solid dissolved. Then 6.69 g (39.11 mmoles) of benzyl bromide in 40 mL of ether was added during 0.5 hours. The stirring was continued for 27 hours. Water (100 mL) was added. The layers were separated. The aqueous layer was extracted with ether (2×75 mL). The combined ether phases were washed with 50 mL of brine and dried over MgSO4. Evaporation of the solvent left 9.17 g of orange oil. The oil was chromatographed on a 700 g column of silica gel. The column was eluted with 1:2 CH2Cl2 -Skellysolve B and 200 mL fractions were collected. The fractions were assayed by silica gel tlc (2×8") (1:2 CH2Cl2 -Skellysolve B). Fractions 10-14 were combined giving 7.26 g (90%) of 1-benzyl-5-chloroindole as a yellow oil.

Workup

  1. additionwas added
  2. dissolutionMost of the solid dissolved
  3. waitThe stirring was continued for 27 hours
  4. customThe layers were separated
  5. extractionThe aqueous layer was extracted with ether (2×75 mL)
  6. washThe combined ether phases were washed with 50 mL of brine
  7. dry with materialdried over MgSO4
  8. customEvaporation of the solvent
  9. waitleft 9.17 g of orange oil
  10. customThe oil was chromatographed on a 700 g column of silica gel
  11. washThe column was eluted with 1:2 CH2Cl2 -Skellysolve B and 200 mL fractions
  12. customwere collected

Sources & evidence

ORD record
ord-0121012381ad40bb9bdeb58d7a76e8eb
Source dataset
uspto-grants-1993_09
Patent number
US05245046

Linked notes

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