2-(Ethoxymethylene)propanedinitrile → 4-Chlorobenzamidine

HRID 2285595Notes

Reaction equation

HRID 2285595 reaction equation
Cl.[Cl:2][C:3]1[CH:11]=[CH:10][C:6]([C:7]([NH2:9])=[NH:8])=[CH:5][CH:4]=1.[Na].C(OC=C(C#N)C#N)C>C(O)C>[Cl:2][C:3]1[CH:11]=[CH:10][C:6]([C:7]([NH2:9])=[NH:8])=[CH:5][CH:4]=1

Participants

5

Reactant 3

HCID 671522-(Ethoxymethylene)propanedinitrileHCID 2034364-Chlorobenzene-1-carboximidamide hydrochlorideHCID 5360545Sodium

Product 1

HCID 2034374-Chlorobenzamidine

Reagents, catalysts & solvents 1

HCID 702EthanolSolvent2×

Procedure

Free p-chlorobenzamidine base is prepared by addition of p-chlorobenzamidine hydrochloride (30.000 g., 0.157 mole) to a solution of sodium (3.795 g., 0.165 mole) in absolute ethanol (400 ml.) in a nitrogen atmosphere. After stirring for one hour, ethoxymethylenemalononitrile (20.151 g., 0.165 mole) is added followed by ethanol (350 ml.) to facilitate stirring. After stirring at ambient temperature for ca. 70 hours, the mixture is refluxed for ten minutes, cooled, filtered and the solid product washed with ethanol (100 ml.), water (2×50 ml.) then dried at 80° C./house vac. then at 100° C./house vac./2 hours. The yield of colorless crystals melting at 267.0°-267.5° C. (uncorr.) is 27.9 g. (77.1%). The initial product is recrystallized from 1,2-dimethoxyethane affording colorless needles melting at 267.0°-267.5° C. (uncorr.) in a yield of 20.160 g. (55.7%). Concentration of the mother liquors afforded two additional crops of colorless needles: first crop (4.525 g., 12.5%), melting at 266.0°-267.5° C. (uncorr.); second crop (1.479 g., 4.1%), melting at 265.0°-265.5° C. (uncorr.).

Workup

  1. stirringto facilitate stirring
  2. stirringAfter stirring at ambient temperature for ca. 70 hours
  3. temperaturethe mixture is refluxed for ten minutes
  4. temperaturecooled
  5. filtrationfiltered
  6. washthe solid product washed with ethanol (100 ml.), water (2×50 ml.)
  7. customthen dried at 80° C./house vac
  8. customat 100° C.
  9. custom2 hours
  10. customThe initial product is recrystallized from 1,2-dimethoxyethane affording colorless needles melting at 267.0°-267.5° C. (uncorr.) in a yield of 20.160 g
  11. customConcentration of the mother liquors afforded two additional crops of colorless needles

Sources & evidence

ORD record
ord-a06d79180c854fceab6bcc95f8970f9c
Source dataset
uspto-grants-1982_04
Patent number
US04323681

Reaction notes

Loading…