Potassium Cyanide → 5-cyanospiro[benzo[b]furan-2(3H), 1'-cyclopropane]-3-one

HRID 894632Notes

Reaction equation

HRID 894632 reaction equation
N[C:2]1[CH:13]=[CH:12][C:5]2[O:6][C:7]3([C:10](=[O:11])[C:4]=2[CH:3]=1)[CH2:9][CH2:8]3.N([O-])=O.[Na+].C(=O)([O-])O.[Na+].[C-:23]#[N:24].[K+]>Cl.C(OCC)(=O)C.C1(C)C=CC=CC=1>[C:23]([C:2]1[CH:13]=[CH:12][C:5]2[O:6][C:7]3([C:10](=[O:11])[C:4]=2[CH:3]=1)[CH2:9][CH2:8]3)#[N:24]

Participants

8

Reactant 4

HCID 9032Potassium CyanideHCID 516892Sodium BicarbonateHCID 12925991HCID 12925991, compoundHCID 23668193Sodium Nitrite

Product 1

HCID 129260375-cyanospiro[benzo[b]furan-2(3H), 1'-cyclopropane]-3-oneYield 75.7%

Reagents, catalysts & solvents 3

HCID 313Hydrochloric AcidSolventHCID 1140TolueneSolventHCID 8857Ethyl AcetateSolvent

Procedure

5-Aminospiro[benzo[b]furan-2(3H),1'-cyclopropane]-3-one (1.75 g.) was dissolved in conc. HCl (2.5 ml.) and ice-water (20 ml.), and to the solution was added dropwise 2 ml of aqueous solution of sodium nitrite (0.7 g.) under ice-cooling. After stirring for one hour and adding toluene (5 ml.), the solution was neutralized with sodium hydrogen carbonate at -20° C. To 18 ml of another aqueous solution of cuprous cyanide prepared from cuprous chloride (2.4 g.) and potassium cyanide (4.4 g.) was added ethyl acetate (20 ml.), and, to the mixture was added, under ice-cooling and stirring, the above neutralized solution of diazonium salt. The mixture was stirred for half an hour at room temperature and further stirred for half an hour at 70° C. The insolubles were removed by filtration, and the filtrate was extracted with ethyl acetate. The extract was washed with aqueous solution of sodium carbonate, diluted hydrochloric acid and water in the order mentioned, and dried. The solvent was evaporated off under reduced pressure, and the obtained residue was recrystallized from methanol to give colorless needles of 5-cyanospiro[benzo[b]furan-2(3H),1'-cyclopropane]-3-one (1.4 g.) m.p. 148°-149° C.

Workup

  1. temperaturecooling
  2. additionto the mixture was added, under ice-
  3. temperaturecooling
  4. stirringstirring
  5. stirringThe mixture was stirred for half an hour at room temperature
  6. stirringfurther stirred for half an hour at 70° C
  7. customThe insolubles were removed by filtration
  8. extractionthe filtrate was extracted with ethyl acetate
  9. washThe extract was washed with aqueous solution of sodium carbonate, diluted hydrochloric acid and water in the order
  10. customdried
  11. customThe solvent was evaporated off under reduced pressure
  12. customthe obtained residue was recrystallized from methanol

Sources & evidence

ORD record
ord-47d955501cda44c8b5106ccf32cb4fe3
Source dataset
uspto-grants-1981_08
Patent number
US04284644

Reaction notes

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