2,6-Dibromopyridine → 6-Bromo-2,3'-bipyridine

HRID 1796071Notes

Reaction equation

HRID 1796071 reaction equation
C([Sn](CCCC)(CCCC)[C:6]1[CH:7]=[N:8][CH:9]=[CH:10][CH:11]=1)CCC.[Br:20][C:21]1[CH:26]=[CH:25][CH:24]=[C:23](Br)[N:22]=1>O1CCCC1.C1C=CC([P]([Pd]([P](C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)([P](C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)[P](C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)=CC=1>[CH3:9][CH2:10][CH2:11][CH:6]([CH3:7])[CH3:21].[Br:20][C:21]1[N:22]=[C:23]([C:6]2[CH:7]=[N:8][CH:9]=[CH:10][CH:11]=2)[CH:24]=[CH:25][CH:26]=1

Participants

6

Reactant 2

HCID 122742,6-DibromopyridineHCID 34838483-(Tributylstannyl)pyridine

Product 2

HCID 78922-MethylpentaneHCID 135464546-Bromo-2,3'-bipyridineYield 41%

Reagents, catalysts & solvents 2

HCID 178418397HCID 178418397, compoundCatalystHCID 8028TetrahydrofuranSolvent

Procedure

3-Tributylstannylpyridine (3.3 g, 9.0 mmol) was added to a degassed solution of 2,6-dibromopyridine (2.0 g, 8.3 mmol) and tetrakis(triphenylphosphine)palladium(0) (0.48 g, 5 mol %) in dry tetrahydrofuran (30 ml), stirred under an atmosphere of nitrogen and heated to reflux for 48 h. After cooling to ambient temperature, solvent was removed in vacuo, the residue dissolved in dichloromethane and purified by chromatography on silica gel eluting with dichloromethane on a gradient of methanol (0-4%). Trituration with isohexane gave 6-bromo-2,3′-bipyridine (0.4 g) as a solid: δH (400 MHz, CDCl3) 7.42 (1H, dd, J 8 and 8), 7.49 (1H, d, J 7), 7.65 (1H, dd, J 7 and 7), 7.73 (1H, d, J 7), 8.35 (1H, m), 8.68 (1H, m), 9.16 (1H, s); m/z (ES+) 235/236 (M++H).

Workup

  1. temperatureheated
  2. temperatureto reflux for 48 h
  3. customsolvent was removed in vacuo
  4. dissolutionthe residue dissolved in dichloromethane
  5. custompurified by chromatography on silica gel eluting with dichloromethane on a gradient of methanol (0-4%)

Sources & evidence

ORD record
ord-2f3b883f4f6c42528ed8e270b86375b3
Source dataset
uspto-grants-2006_04
Patent number
US07030128B2

Reaction notes

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