Phosgene → Bis(3-isocyanatopropyl)tetramethyldisiloxane

HRID 2412534Notes

Reaction equation

HRID 2412534 reaction equation
[NH2:1][CH2:2][CH2:3][CH2:4][Si:5]([CH2:12][CH2:13][CH2:14][NH2:15])([CH3:11])[O:6][Si:7]([CH3:10])([CH3:9])[CH3:8].[C:16](Cl)(Cl)=[O:17].[C:20](OCCCC)(=[O:22])C>>[N:1]([CH2:2][CH2:3][CH2:4][Si:5]([CH2:12][CH2:13][CH2:14][N:15]=[C:16]=[O:17])([CH3:11])[O:6][Si:7]([CH3:10])([CH3:9])[CH3:8])=[C:20]=[O:22]

Participants

4

Reactant 3

HCID 6371Phosgene4×HCID 31272Butyl Acetate2×HCID 21585087Bis(aminopropyl)tetramethyldisiloxane

Product 1

HCID 20431620Bis(3-isocyanatopropyl)tetramethyldisiloxane

Conditions

Temperature
10 °C

Procedure

Twenty parts of bis(3-aminopropyl)tetramethyldisiloxane obtained in Example 1, (1) was dissolved in 400 parts of butyl acetate. Thirty parts of butyl acetate was put in a flask equipped with a stirrer, a dropping funnel, a reflux condenser, a thermometer and a phosgene introducing tube, and cooled to 10° C. with an ice bath. Phosgene passed through the flask, and the polyamine solution prepared as above was added dropwise from the dropping funnel over the course of 30 minutes. After the addition, phosgene was further passed through the flask for 30 minutes to continue the reaction between the polyamine and phosgene. The ice bath was then replaced by an oil bath, and the reaction mixture was heated to 110° C. The reaction was continued by passing phosgene for 1 hour. After the reaction, dry nitrogen was passed through the flask at 110° C. to remove dissolved gases. The unreacted materials and the solvent were evaporated off, and the residue was distilled under reduced pressure to give 4 parts of bis(3-isocyanatopropyl)tetramethyldisiloxane of the following formula having a boiling point of 131° C. at 2 mmHg. ##STR41##

Workup

  1. customequipped with a stirrer, a dropping funnel, a reflux condenser
  2. additionabove was added dropwise from the dropping funnel over the course of 30 minutes
  3. temperaturethe reaction mixture was heated to 110° C
  4. customfor 1 hour
  5. customAfter the reaction, dry nitrogen
  6. customwas passed through the flask at 110° C.
  7. customto remove
  8. dissolutiondissolved gases
  9. customThe unreacted materials and the solvent were evaporated off
  10. distillationthe residue was distilled under reduced pressure

Sources & evidence

ORD record
ord-c773b4d6fefa42299d2b25b639cc593c
Source dataset
uspto-grants-1985_01
Patent number
US04493714

Reaction notes

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