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

HRID 1710517Notes

Reaction equation

HRID 1710517 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-30a85aec32ae4a9bbcb8b4c2484b1c5d
Source dataset
uspto-grants-2010_09
Patent number
US07790716B2

Reaction notes

Loading…