Methane → Caprolactam

HRID 441938Notes

Reaction equation

HRID 441938 reaction equation
C([N:9]1[CH2:15][CH2:14][CH2:13][CH2:12][CH:11]([Cl:16])[C:10]1=[O:17])(=O)C1C=CC=CC=1.C.[C:19]1(=[O:26])[NH:25][CH2:24][CH2:23][CH2:22][CH2:21][CH2:20]1>C1C=CC(Cl)=C(Cl)C=1>[Cl:16][CH:11]1[CH2:12][CH2:13][CH2:14][CH2:15][NH:9][C:10]1=[O:17].[C:19]1(=[O:26])[NH:25][CH2:24][CH2:23][CH2:22][CH2:21][CH2:20]1

Participants

6

Reactant 3

HCID 297MethaneHCID 7768CaprolactamHCID 28219126536-94-72×

Product 2

HCID 7768CaprolactamHCID 3516023-chloroazepan-2-one

Reagents, catalysts & solvents 1

HCID 72391,2-DichlorobenzeneSolvent2×

Procedure

The ODCB solution of N-benzoyl-α-chloro-ε-caprolactam is passed through a charcoal bed to remove tars as impurities. It is then passed into another reaction vessel where 9718 parts (86 mols) of ε-caprolactam are added. The transamidation is conducted by heating and stirring the ODCB solution at 140° C. for 2 hours. The solution is then cooled to 5° C. for 1 hour whereupon 21,000 parts (82 mols) N-benzoyl-α-chloro-ε-caprolactam precipitates out of the solution. The N-benzoyl-α-chloro-ε-caprolactam is filtered off and saved for recycle. The ODCB solution is then extracted with 250,000 parts 8 weight percent aqueous hydrochloric acid to remove α-chloro-ε-caprolactam and residual ε-caprolactam. The aqueous hydrochloric acid is then extracted countercurrently with 250,000 parts chloroform, and the chloroform extract evaporated to yield 10,915 parts (74 mols) of α-chloro-ε-caprolactam and 1356 parts (12 mols) of ε-caprolactam. The ε-caprolactam is separated from the α-chloro-ε-caprolactam by fractional distillation under vacuum and recycled to the transamidation step.

Workup

  1. customto remove tars as impurities
  2. customIt is then passed into another reaction vessel
  3. temperatureby heating
  4. customprecipitates out of the solution
  5. filtrationThe N-benzoyl-α-chloro-ε-caprolactam is filtered off
  6. extractionThe ODCB solution is then extracted with 250,000 parts 8 weight percent aqueous hydrochloric acid
  7. customto remove α-chloro-ε-caprolactam and residual ε-caprolactam
  8. extractionThe aqueous hydrochloric acid is then extracted countercurrently with 250,000 parts chloroform
  9. extractionthe chloroform extract
  10. customevaporated

Sources & evidence

ORD record
ord-b7abaae0f6d944b8950128c24fe63ab4
Source dataset
uspto-grants-1977_08
Patent number
US04044001

Reaction notes

Loading…