2,6-Dibromopyridine → 2-Bromo-6-(thiophen-3-yl)pyridine

HRID 1796089Notes

Reaction equation

HRID 1796089 reaction equation
Br[C:2]1[CH:7]=[CH:6][CH:5]=[C:4]([Br:8])[N:3]=1.[S:9]1[CH:13]=[CH:12][C:11](B(O)O)=[CH:10]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>[Br:8][C:4]1[CH:5]=[CH:6][CH:7]=[C:2]([C:11]2[CH:12]=[CH:13][S:9][CH:10]=2)[N:3]=1

Participants

5

Reactant 2

HCID 122742,6-DibromopyridineHCID 581760Thiophene-3-boronic acid

Product 1

HCID 221807762-Bromo-6-(thiophen-3-yl)pyridineYield 58.7%

Reagents, catalysts & solvents 2

HCID 178418397HCID 178418397, compoundCatalystHCID 8028TetrahydrofuranSolvent

Procedure

Tetrakis(triphenylphosphine)palladium(0) (5 mol %) was added to a degassed and stirred mixture of 2,6-dibromopyridine (3.78 g, 15.6 mmol) and thiophene-3-boronic acid (2.20 g, 16.8 mmol) in tetrahydrofuran (40 ml) under an atmosphere of nitrogen then heated to reflux for 24 h. Solvent was removed in vacuo and purification by chromatography on silica gel eluting with a gradient of diethyl ether-isohexane (5-10%) gave 2-bromo-6-(thien-3-yl)pyridine (2.20 g) as a white solid: δH (400 MHz, CDCl3) 7.32-7.41 (2H, m), 7.53-7.55 (2H, m), 7.61-7.64 (1H, m), 7.94-7.96 (1H, m); m/z (ES+) 240/242 (M++H).

Workup

  1. customa degassed
  2. temperaturethen heated
  3. temperatureto reflux for 24 h
  4. customSolvent was removed in vacuo and purification by chromatography on silica gel eluting with a gradient of diethyl ether-isohexane (5-10%)

Sources & evidence

ORD record
ord-3cd997a4ed7a41ea8b4988e4b237e8bb
Source dataset
uspto-grants-2006_04
Patent number
US07030128B2

Reaction notes

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