1,4-Bis(1,2-dibromoethyl)benzene → 1,4-Diethynylbenzene

HRID 1086788Notes

Reaction equation

HRID 1086788 reaction equation
Br[CH:2]([C:5]1[CH:10]=[CH:9][C:8]([CH:11](Br)[CH2:12]Br)=[CH:7][CH:6]=1)[CH2:3]Br.CC(C)([O-])C.[K+]>C(O)(C)(C)C>[C:2]([C:5]1[CH:10]=[CH:9][C:8]([C:11]#[CH:12])=[CH:7][CH:6]=1)#[CH:3]

Participants

4

Reactant 2

HCID 970181,4-Bis(1,2-dibromoethyl)benzeneHCID 23665647Potassium tert-butoxide

Product 1

HCID 1204631,4-DiethynylbenzeneYield 79.9%

Reagents, catalysts & solvents 1

HCID 6386tert-ButanolSolvent

Procedure

In a 2 liter-volume four-necked flask having the same equipments as used in 1) above were charged 100 g of 1,4-bis(1,2-dibromoethyl)benzene, 103 g of potassium t-butoxide and 1 liter of t-butyl alcohol, and the mixture was stirred taking care not to rapidly raise the temperature by cooling on an ice bath. The stirring was continued while gradually elevating the temperature finally to a refluxing temperature, at which stirring was conducted for 1.5 hours. The reaction mixture was poured into 6 liters of ice-water, and the thus formed precipitate was filtered by suction. Purification by sublimation (60°±3° C., 1 to 2 mmHg) gave 22.4 g of crystals of p-diethynylbenzene ##STR8## having a melting point of 96.5° C.

Workup

  1. temperatureto rapidly raise the temperature
  2. temperatureby cooling on an ice bath
  3. stirringat which stirring
  4. filtrationthe thus formed precipitate was filtered by suction
  5. customPurification by sublimation (60°±3° C., 1 to 2 mmHg)

Sources & evidence

ORD record
ord-a820d6d45f0b4a019b31ee3b25c40641
Source dataset
uspto-grants-1991_07
Patent number
US05032489

Reaction notes

Loading…