Ethanol → HCID 21283437, compound

HRID 2232265Notes

Reaction equation

HRID 2232265 reaction equation
OS(O)(=O)=O.O.[CH2:7]([OH:9])[CH3:8].[Cl:10][C:11]1[CH:16]=[C:15]([Cl:17])[CH:14]=[CH:13][C:12]=1[C:18](=[CH2:22])[C:19](N)=[O:20]>C(Cl)Cl.[Cu]>[CH2:7]([O:9][C:19](=[O:20])[C:18]([C:12]1[CH:13]=[CH:14][C:15]([Cl:17])=[CH:16][C:11]=1[Cl:10])=[CH2:22])[CH3:8]

Participants

7

Reactant 4

HCID 702EthanolHCID 962Water2×HCID 1118Sulfuric AcidHCID 21283441HCID 21283441, compound

Product 1

HCID 21283437HCID 21283437, compound

Reagents, catalysts & solvents 2

HCID 23978CopperCatalystHCID 6344DichloromethaneSolvent

Conditions

Temperature
100 °C

Procedure

Add the cyanohydrin prepared in Example 5(a), 2,4-dichloroacetophenone cyanohydrin-O-trimethylsilylether, (75 g) dropwise to a solution of concentrated H2SO4 containing 4% SO3 (60 mL) and 250 mg of copper powder at 40° C. During the addition, maintain the reaction temperature between 80°-85° C. (water bath). After all cyanohydrin is added, raise the temperature to 100° C. and heat the reaction mixture at this temperature for 30 min. Cool the reaction mixture to 90° C. and carefully treat with water (26 mL) and ethanol (60 mL). Heat the mixture at 100° C. for 15 hrs, cool and dilute with ice cold water (200 mL). Separate the organic layer, dilute with CH2Cl2 (100 mL) and wash with brine (100 mL). Extract the combined aqueous phase containing solids twice with EtOAc (400 mL), wash with saturated NaHCO3, water (100 mL each) and dry over Na2SO4. Eyaporate EtOAc in vacuo to give an oil containing a crystalline solid. Dilute this residue with a small yolume of CH2Cl2 -separated crystals of α-(2,4-dichlorophenyl)-α-methyleneacetamide which were collected by filtration (26 g). Combine the filtrate with the organic layer obtained earlier and chromatograph the concentrate on silica gel (300 g) to provide ethyl-α-(2,4-dichlorophenyl)-α-methyleneacetate.

Workup

  1. additionDuring the addition
  2. temperatureheat the reaction mixture at this temperature for 30 min
  3. temperatureCool the reaction mixture to 90° C.
  4. temperatureHeat the mixture at 100° C. for 15 hrs
  5. temperaturecool
  6. customSeparate the organic layer
  7. additiondilute with CH2Cl2 (100 mL)
  8. washwash with brine (100 mL)
  9. extractionExtract the combined aqueous phase
  10. additioncontaining solids twice with EtOAc (400 mL)
  11. washwash with saturated NaHCO3, water (100 mL each)
  12. dry with materialdry over Na2SO4
  13. customEyaporate EtOAc in vacuo to give an oil
  14. additioncontaining a crystalline solid
  15. filtrationwere collected by filtration (26 g)
  16. customCombine the filtrate with the organic layer obtained earlier
  17. concentrationchromatograph the concentrate on silica gel (300 g)

Sources & evidence

ORD record
ord-d2f772d598104f5e97ca0cd33c6b2de3
Source dataset
uspto-grants-1988_11
Patent number
US04788190

Reaction notes

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