Benzyl Chloride → Benzyl isocyanate

HRID 1605070Notes

Reaction equation

HRID 1605070 reaction equation
[Cl-].[Ca+2].[Cl-].[Cl-].[Ca+2].[Cl-].[CH3:7][N:8](C)[CH:9]=[O:10].C(Cl)[C:13]1[CH:18]=[CH:17][CH:16]=[CH:15][CH:14]=1.[O-]C#N.[Na+]>CN(C)C=O>[CH2:7]([N:8]=[C:9]=[O:10])[C:13]1[CH:18]=[CH:17][CH:16]=[CH:15][CH:14]=1

Participants

6

Reactant 4

HCID 7503Benzyl ChlorideHCID 517096Sodium CyanateHCID 5284359Calcium ChlorideHCID 86733214HCID 86733214, compound

Product 1

HCID 76639Benzyl isocyanate

Reagents, catalysts & solvents 1

HCID 6228DimethylformamideSolvent2×

Procedure

100 g of anhydrous calcium chloride powder was added to 100 g of dimethylformamide with agitation, and the mixture was heated to form a paste. The paste was evaporated to dryness under a reduced pressure and below 50°C. to obtain a coarse white crystalline powder. Analysis showed that the powder was a calcium chloride-dimethylformamide compound. 20 g of this white crystalline powder was dissolved in 300 g of dimethylformamide, and 126.6 g of benzyl chloride was added to the solution and 75 g of sodium cyanate powder (having a purity of 98 %) was added to the solution with agitation, at an elevated temperature of 100°C., over a period of 4 hours. When 5 hours had passed from the start of the reaction, the reaction mixtures was treated under reduced pressure to recover dimethylformamide by distillation, and the residue was extracted with benzene and the benzene extract was distilled under reduced pressure to obtain 113 g of benzyl isocyanate (the yield being about 85 %). When the above reaction was repeated without adding 20 g of the white crystalline powder, tribenzyl isocyanurate was obtained in a yield of about 70 %, instead of benzyl isocyanate.

Workup

  1. temperaturethe mixture was heated
  2. customto form a paste
  3. customThe paste was evaporated to dryness under a reduced pressure and below 50°C.
  4. customto obtain a coarse white crystalline powder
  5. additionwas added to the solution with agitation, at an elevated temperature of 100°C., over a period of 4 hours
  6. customWhen 5 hours had passed from the start of the reaction
  7. customthe reaction mixtures
  8. additionwas treated under reduced pressure
  9. customto recover dimethylformamide
  10. distillationby distillation
  11. extractionthe residue was extracted with benzene
  12. extractionthe benzene extract
  13. distillationwas distilled under reduced pressure

Sources & evidence

ORD record
ord-fa5481cfd637429f898951d524a93e54
Source dataset
uspto-grants-1976_04
Patent number
US03948966

Reaction notes

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