Methyl iodide → 5-Bromo-N-methylpyridin-2-amine

HRID 2112651Notes

Reaction equation

HRID 2112651 reaction equation
[H-].[Na+].[NH2:3][C:4]1[CH:9]=[CH:8][C:7]([Br:10])=[CH:6][N:5]=1.[CH3:11]I>CN(C=O)C>[Br:10][C:7]1[CH:8]=[CH:9][C:4]([NH:3][CH3:11])=[N:5][CH:6]=1

Participants

5

Procedure

To a suspension of NaH (60% dispersion in mineral oil, 0.44 g, 11 mmole) in dry DMF (40 mL) was added solid 2-amino-5-bromopyridine (1.73 g, 10 mmole) in portions over 5-10 min. Gas evolution was allowed to subside between additions. The resulting amber mixture was stirred for 15 min, then methyl iodide (0.61 mL, 10 mmole) was added all at once. The reaction mixture was stirred at RT overnight, then was concentrated in vacuo. The residue was diluted with 5% NH4Cl (30 mL) and the mixture was extracted with CH2Cl2. The combined organic extracts were washed with brine, dried (MgSO4), and concentrated. Flash chromatography on silica gel (3% MeOH/CH2Cl2) separated the products. 5-Bromo-2-(methylamino)pyridine (0.60 g, 32%) was obtained as a semisolid: TLC (3% MeOH/CH2Cl2) Rf 0.35; MS (ES) m/e 187 (M+H)+. 5-Bromo-2-(dimethylamino)pyridine (0.70 g, 34%) was obtained as a semisolid: TLC (3% MeOH/CH2Cl2) Rf 0.77; MS (ES) m/e 201 (M+H)+.

Workup

  1. stirringThe reaction mixture was stirred at RT overnight
  2. concentrationwas concentrated in vacuo
  3. additionThe residue was diluted with 5% NH4Cl (30 mL)
  4. extractionthe mixture was extracted with CH2Cl2
  5. washThe combined organic extracts were washed with brine
  6. dry with materialdried (MgSO4)
  7. concentrationconcentrated
  8. customFlash chromatography on silica gel (3% MeOH/CH2Cl2) separated the products

Sources & evidence

ORD record
ord-ead0cc7f9e7447119dcdaa06639ca303
Source dataset
uspto-grants-2009_04
Patent number
US07524843B2

Reaction notes

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