Iodine → 3-(2-Ethylhexyl)thiophene

HRID 540966Notes

Reaction equation

HRID 540966 reaction equation
[Mg].II.[CH2:4]([CH:6]([CH2:9][CH2:10][CH2:11][CH3:12])[CH2:7]Br)[CH3:5].Br[C:14]1[CH:18]=[CH:17][S:16][CH:15]=1>C1COCC1.Cl[Ni]1(Cl)[P](C2C=CC=CC=2)(C2C=CC=CC=2)CCC[P]1(C1C=CC=CC=1)C1C=CC=CC=1>[CH2:4]([CH:6]([CH2:9][CH2:10][CH2:11][CH3:12])[CH2:7][C:14]1[CH:18]=[CH:17][S:16][CH:15]=1)[CH3:5]

Participants

7

Reactant 4

HCID 807IodineHCID 133833-BromothiopheneHCID 868042-Ethylhexyl bromideHCID 5462224Magnesium

Product 1

HCID 144195433-(2-Ethylhexyl)thiopheneYield 62.2%

Reagents, catalysts & solvents 2

HCID 178418745HCID 178418745, compoundCatalystHCID 8028TetrahydrofuranSolvent3×

Procedure

To a mixture of magnesium turnings (3.0 g, 0.12 mol), anhydrous THF (20 mL) and a small amount of iodine in a 300 mL flask, a solution of 2-ethylhexylbromide (23.5 g, 0.12 mol) in anhydrous THF (35 mL) was added slowly at 0° C. under N2. After refluxing for 1 h, the solution was added dropwise to a mixture of 3-bromothiophene (15 g, 0.09 mol, (9-3)), Ni(dppp)Cl2 (0.51 g, 0.001 mmol) and anhydrous THF (35 mL) placed in a 500 mL flask at 0° C. After the mixture was stirred overnight at room temperature, the reaction was quenched by pouring cold HCl aq. (2 N) into the mixture. The product was extracted with CHCl3 and dried over anhydrous Mg2SO4. The crude product was further purified by column chromatography using hexane as the eluent to give (9-4) as a clear liquid (11 g, 61%). 1H NMR (CDCl3, 300 MHz, ppm): 7.20-7.22 (m, 1H), 6.88-6.90 (m, 2H), 2.56 (d, 2H, J=6.9 Hz), 1.49-1.57 (m, 1H), 1.24-1.33 (m, 8H), 0.86-0.89 (m, 6H)

Workup

  1. temperatureAfter refluxing for 1 h
  2. customplaced in a 500 mL flask at 0° C
  3. customthe reaction was quenched
  4. additionby pouring cold HCl aq. (2 N) into the mixture
  5. extractionThe product was extracted with CHCl3
  6. dry with materialdried over anhydrous Mg2SO4
  7. customThe crude product was further purified by column chromatography

Sources & evidence

ORD record
ord-70f24771788e40fd911e4e5ba96a1311
Source dataset
uspto-grants-2014_10
Patent number
US08871884B2

Reaction notes

Loading…