Melatonin → 2-Bromomelatonin

HRID 741701Notes

Reaction equation

HRID 741701 reaction equation
[Br:1]N1C(=O)CCC1=O.[CH3:9][C:10]([NH:12][CH2:13][CH2:14][C:15]1[C:19]2[CH:20]=[C:21]([O:24][CH3:25])[CH:22]=[CH:23][C:18]=2[NH:17][CH:16]=1)=[O:11].[OH-].[Na+]>C(O)(=O)C>[CH3:9][C:10]([NH:12][CH2:13][CH2:14][C:15]1[C:19]2[CH:20]=[C:21]([O:24][CH3:25])[CH:22]=[CH:23][C:18]=2[NH:17][C:16]=1[Br:1])=[O:11]

Participants

5

Reactant 3

HCID 896MelatoninHCID 14798Sodium HydroxideHCID 67184N-bromobutanimide

Product 1

HCID 1267312-BromomelatoninYield 30%

Reagents, catalysts & solvents 1

HCID 176Acetic AcidSolvent

Procedure

N-bromo succinimide (0.89 g, 5 mmol) was added to a solution of melatonin (1.16 g, 5 mmol) in acetic acid (20 mL). The reaction mixture was stirred under N2 at room temperature for 4 h, then cooled at 0° C., neutralized with a 50% solution of NaOH and extracted with ethyl acetate. The combined organic layers were washed with NaCl solution, dried (Na2SO4) and concentrated. Purification by flash chromatography (silica gel; ethyl acetate/cyclohexane 6:4) and crystallization gave 0.467 g (30% yield) of 4k as white solid, mp 141°-142° C. IR νmax : 3460, 3300, 1650. 1H NMR: 1.99 (s, 3H, COCH3); 2.92(t, 2H, β -CH2), 3.54(q, 2H, α-CH2), 3.86(s, 3H, OCH3), 5.53(br s, 1H, NH), 6.85-7.23(m, 3Harom), 8.15(br s, 1H, NHindole).

Workup

  1. temperaturecooled at 0° C.
  2. extractionextracted with ethyl acetate
  3. washThe combined organic layers were washed with NaCl solution
  4. dry with materialdried (Na2SO4)
  5. concentrationconcentrated
  6. customPurification
  7. customby flash chromatography (silica gel; ethyl acetate/cyclohexane 6:4) and crystallization

Sources & evidence

ORD record
ord-c4776d20035f4aa29bf3cb03a8961e64
Source dataset
uspto-grants-1996_09
Patent number
US05552428

Reaction notes

Loading…