Ethylene Glycol → HCID 67857991, compound

HRID 258052Notes

Reaction equation

HRID 258052 reaction equation
[C:1]([O:13][CH3:14])(=[O:12])[C:2]1[CH:11]=[CH:10][C:5]([C:6]([O:8][CH3:9])=[O:7])=[CH:4][CH:3]=1.[CH2:15](O)CO>>[CH2:15]=[CH:6][C:5]1[CH:4]=[CH:3][CH:2]=[CH:11][CH:10]=1.[C:6]1(=[O:7])[O:8][CH2:9][CH2:14][O:13][C:1](=[O:12])[C:2]2[CH:11]=[CH:10][C:5]1=[CH:4][CH:3]=2

Participants

3

Reactant 2

HCID 174Ethylene GlycolHCID 8441Dimethyl terephthalate

Product 1

HCID 67857991HCID 67857991, compound

Conditions

Temperature
190 °C

Procedure

Dimethyl terephthalate is recrystallized from dried ethanol. 30 g (0.154 mol) of the dimethyl terephthalate and 30 ml of TCB are added to a 250 ml three-neck round bottom flask fitted with a nitrogen stream inlet and outlet, a magnet stirrer, a dropping funnel, and a condenser, and heated to about 190° C. 20 g of hydroxy-terminated polystyrene, 70 ml of TCB, and 2 ml of catalyst solution (titanium butoxide, magnesium acetate, methanol, and butanediol solution) are introduced dropwise into the reactor over 3 hours. After refluxing for one and one-half hours and confirming the absence of hydroxy-terminated polystyrene by thin layer chromotography analysis, the reactor is cooled to below 190° C., and 10.54 g (0.170 mol) of ethylene glycol is added. The contents are kept refluxing at about 214° C. for 10 hours while maintaining a nitrogen stream purge. The reaction mixture is thereafter cooled, and the crude styrene-ethylene terephthalate product precipitated in excess methanol before being dried in a vacuum oven for 24 hours. The crude condensation product is finally extracted with cyclohexane for 12 hours to remove unreacted or chain unextended polystyrene.

Workup

  1. customDimethyl terephthalate is recrystallized from dried ethanol
  2. customfitted with a nitrogen stream inlet and outlet, a magnet stirrer, a dropping funnel, and a condenser
  3. custom20 g of hydroxy-terminated polystyrene, 70 ml of TCB, and 2 ml of catalyst solution (titanium butoxide, magnesium acetate, methanol, and butanediol solution)
  4. additionare introduced dropwise into the reactor over 3 hours
  5. temperatureAfter refluxing for one and one-half hours
  6. customterminated polystyrene by thin layer chromotography analysis
  7. temperaturethe reactor is cooled to below 190° C.
  8. temperatureThe contents are kept refluxing at about 214° C. for 10 hours
  9. temperaturewhile maintaining a nitrogen stream
  10. custompurge
  11. temperatureThe reaction mixture is thereafter cooled
  12. customthe crude styrene-ethylene terephthalate product precipitated in excess methanol
  13. custombefore being dried in a vacuum oven for 24 hours
  14. customThe crude condensation product
  15. extractionis finally extracted with cyclohexane for 12 hours
  16. customto remove unreacted

Sources & evidence

ORD record
ord-d14d6ae90b614ecaa2c2adfca573287c
Source dataset
uspto-grants-1993_11
Patent number
US05264491

Reaction notes

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