3,4-Dibromothiophene → HCID 57734457, compound

HRID 1686170Notes

Reaction equation

HRID 1686170 reaction equation
Br[C:2]1[C:6]([Br:7])=[CH:5][S:4][CH:3]=1.[CH3:8][Si:9]([CH3:16])([CH3:15])[O:10][C:11]#[C:12][CH2:13][CH3:14]>[Cu](I)I.C1(P(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1.C(N(CC)CC)C>[Br:7][C:6]1[C:2]([C:14]#[C:13][CH2:12][CH2:11][O:10][Si:9]([CH3:16])([CH3:15])[CH3:8])=[CH:3][S:4][CH:5]=1

Participants

6

Reactant 2

HCID 184523,4-DibromothiopheneHCID 86631013HCID 86631013, compound

Product 1

HCID 57734457HCID 57734457, compoundYield 23.1%

Reagents, catalysts & solvents 3

HCID 11776TriphenylphosphineCatalystHCID 83717Copper iodideCatalystHCID 8471TriethylamineSolvent

Conditions

Temperature
60 °C

Procedure

Into a 250 mL 4 necked RB flask equipped with a magnetic stirring bar, thermometer, rubber septum, argon inlet and reflux condenser with argon outlet (tubed to a silicon oil bubbler) is added 55.0 g (229 mmol) of 3,4-dibromothiophene, 15.6 g of triethylamine, 9.75 g (68.5 mmol) of trimethylsiloxy-1-butyne, 170 mg of triphenylphosphine, 140 mg of copper iodide and 490 mg of dichlorobis(triphenylphosphine) palladium(II). The mixture is heated with a silicon oil bath to 60° C. under argon with stirring for 2 hrs. The cooled mixture is then concentrated on a rotary evaporator at reduced pressure and the residue taken up in 200 mL of hexanes and washed with 2×25 mL of water and the pentane phase dried over sodium sulfate and then concentrated on a rotary evaporator. The residue was chromatographed through neutral silica gel eluted with 2/1 methylenechloride/hexanes to yield 4.8 g of 3-bromo-4(trimethylsiloxybutynyl)thiophene as a light yellow oil which was used directly to prepare 2-hydroxyethylselenolo[2,3-c]thiophene.

Workup

  1. temperaturethermometer, rubber septum, argon inlet and reflux condenser with argon outlet (
  2. concentrationThe cooled mixture is then concentrated on a rotary evaporator at reduced pressure
  3. washwashed with 2×25 mL of water
  4. dry with materialthe pentane phase dried over sodium sulfate
  5. concentrationconcentrated on a rotary evaporator
  6. customThe residue was chromatographed through neutral silica gel
  7. washeluted with 2/1 methylenechloride/hexanes

Sources & evidence

ORD record
ord-0af33d1bcad64420a4280674c53fecad
Source dataset
uspto-grants-2012_04
Patent number
US08148548B2

Reaction notes

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