Chloroform → 5,5'-Diacetyl-2,2'-bithiophene

HRID 235233

Reaction equation

HRID 235233 reaction equation
[C:1]([C:4]1[S:5][C:6](Br)=[CH:7][CH:8]=1)(=[O:3])[CH3:2].C[Sn](C)C.C[Sn](C)C.C(Cl)(Cl)Cl>C1(C)C=CC=CC=1.[Pd].C1(P(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1.C1(P(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1.C1(P(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1.C1(P(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1>[C:1]([C:4]1[S:5][C:6]([C:6]2[S:5][C:4]([C:1](=[O:3])[CH3:2])=[CH:8][CH:7]=2)=[CH:7][CH:8]=1)(=[O:3])[CH3:2]

Participants

6

Reactant 3

HCID 6212ChloroformHCID 793352-Acetyl-5-bromothiopheneHCID 6327618Hexamethylditin

Product 1

HCID 3058905,5'-Diacetyl-2,2'-bithiophene

Reagents, catalysts & solvents 2

HCID 11979704Tetrakis(triphenylphosphine)palladiumCatalystHCID 1140TolueneSolvent3×

Conditions

Temperature
-5 °C

Procedure

To a slurry of 1 g tetrakis(triphenyl phosphine) Palladium (0) in 30 ml of dry toluene was added a solution of 6.26 g (30.5 mmol) of 2-acetyl-5-bromo thiophene in 30 ml of dry toluene under argon. The reaction was heated to reflux and to this solution was added dropwise a solution of 5 g (15.26 mmol) of hexamethylditin (99%) in 50 ml toluene (dry) over a period of 1.5 h. The reaction mixture was refluxed for another 6 h and then cooled down to -5° C. Light yellow crystals of the product were isolated by suction filtration and were washed with hexane. The product was then continuously extracted through Whatman filter paper #42 with dioxane using a soxhlet apparatus until all of the product was dissolved and collected in the boiling flask. Slow cooling of the dioxane solution resulted in needle shaped light yellow crystals of the monomer which were separated by suction filtration and dried in vacuum. A Yield of 2.56 g (67%) having the following characteristics was obtained: mp 235° C. (lit. mp 233.5°-234° C.); UV/vis λmax (CHCl3): 367 (log ε=4.19), 262 (3.57); FT-IR (KBr,cm-1): 3070, 1797 1656, 1611, 1511, 1433, 1361, 1302, 1270, 1089, 1036, 1020, 937, 897, 881, 792, 745, 673, 611, 593, 555, 463, 442; 1H NMR (CDCl3 300 MHz, TMS) δ 2.58 (s,6H), 7.30 (d,2H), 7.62 (d,2H). Anal. calcd. for C12H10S2 : C, 57.58; H, 4.03; N, 0.0. Found: C, 57.48; H, 3.87; N, 0.0.

Workup

  1. temperatureThe reaction was heated
  2. temperatureto reflux and to this solution
  3. temperatureThe reaction mixture was refluxed for another 6 h
  4. customLight yellow crystals of the product were isolated by suction filtration
  5. washwere washed with hexane
  6. extractionThe product was then continuously extracted through Whatman
  7. filtrationfilter paper #42 with dioxane using a soxhlet apparatus until all of the product
  8. dissolutionwas dissolved
  9. customcollected in the boiling flask
  10. temperatureSlow cooling of the dioxane solution
  11. customresulted in needle
  12. customwere separated by suction filtration
  13. customdried in vacuum
  14. customwas obtained

Sources & evidence

ORD record
ord-dcb9dd4c714c44d78bc9702ad61dfc07
Source dataset
uspto-grants-1997_01
Patent number
US05597890

Linked notes

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