Chlorotrimethylsilane → Silane, (4-bromophenyl)trimethyl-

HRID 64621Notes

Reaction equation

HRID 64621 reaction equation
[Br:1][C:2]1[CH:7]=[CH:6][C:5](Br)=[CH:4][CH:3]=1.C([Li])CCC.[CH3:14][Si:15]([CH3:18])([CH3:17])Cl>CCOCC.CCCCCC>[Br:1][C:2]1[CH:7]=[CH:6][C:5]([Si:15]([CH3:18])([CH3:17])[CH3:14])=[CH:4][CH:3]=1

Participants

6

Reactant 3

HCID 6397ChlorotrimethylsilaneHCID 78041,4-DibromobenzeneHCID 178418339Butyllithium

Product 1

HCID 138897Silane, (4-bromophenyl)trimethyl-

Reagents, catalysts & solvents 2

HCID 3283Diethyl EtherSolvent2×HCID 8058HexaneSolvent

Procedure

Under argon, 94.4 g of p-dibromobenzene is cooled to -20° C. in 400 ml of absolute ether. To the solution is added dropwise 255 ml of 15% butyllithium in hexane so that the temperature does not rise above -10° C. Then the mixture is agitated for one hour at room temperature. After a negative Gilman test (H. Gilman, J. Swiss, J. Amer. Chem. Soc. 62: 1847 [1940]), the mixture is again cooled to -20° C. and 46 ml of trimethylchlorosilane in 200 ml of absolute ether is added dropwise thereto so that the temperature does not exceed -10° C. After the addition step is finished, the mixture is stirred for 16 hours at room temperature and another hour under reflux. The thus-formed precipitate is suctioned off and thoroughly washed with ether. The resultant filtrate is concentrated and then distilled with a water-jet aspirator, thus producing 65.52 g of p-bromotrimethylsilylbenzene, bp (16 torr) 103°-110° C.

Workup

  1. customdoes not rise above -10° C
  2. temperatureAfter a negative Gilman test (H. Gilman, J. Swiss, J. Amer. Chem. Soc. 62: 1847 [1940]), the mixture is again cooled to -20° C.
  3. customdoes not exceed -10° C
  4. additionAfter the addition step
  5. stirringthe mixture is stirred for 16 hours at room temperature and another hour
  6. temperatureunder reflux
  7. washthoroughly washed with ether
  8. concentrationThe resultant filtrate is concentrated
  9. distillationdistilled with a water-jet aspirator

Sources & evidence

ORD record
ord-380ef2b45f9e43889dd62b604dbfb785
Source dataset
uspto-grants-1986_09
Patent number
US04609651

Reaction notes

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