Cyanoacetic acid → trans-3-(4-oxo-4H-1-benzopyran-3-yl)-acrylonitrile

HRID 26660

Reaction equation

HRID 26660 reaction equation
[O:1]=[C:2]1[C:7]2[CH:8]=[CH:9][CH:10]=[CH:11][C:6]=2[O:5][CH:4]=[C:3]1[CH:12]=O.[C:14]([CH2:16]C(O)=O)#[N:15]>N1C=CC=CC=1>[O:1]=[C:2]1[C:7]2[CH:8]=[CH:9][CH:10]=[CH:11][C:6]=2[O:5][CH:4]=[C:3]1/[CH:12]=[CH:16]/[C:14]#[N:15]

Participants

4

Reactant 2

HCID 9740Cyanoacetic acidHCID 871123-Formylchromone

Product 1

HCID 12330012trans-3-(4-oxo-4H-1-benzopyran-3-yl)-acrylonitrile

Reagents, catalysts & solvents 1

HCID 1049PyridineSolvent

Conditions

Temperature
110 °C

Procedure

A mixture of 10.44 parts of 4-oxo-4H-1-benzopyran-3- carboxaldehyde and 5.4 parts of cyanoacetic acid are heated in an oil bath at 110° C., and to the mixture 25 volume parts of pyridine are added dropwise over about 30 seconds, after which time the whole mixture is further heated for 8 minutes. After cooling, the separated crystals are recovered by filtration, treated with activated carbon and recrystallized three times from ethanol. This procedure yields trans-3-(4-oxo-4H-1-benzopyran-3-yl)-acrylonitrile as pale-yellowish prisms. Melting point: 192°-194° C.

Workup

  1. temperatureafter which time the whole mixture is further heated for 8 minutes
  2. temperatureAfter cooling
  3. filtrationthe separated crystals are recovered by filtration
  4. additiontreated with activated carbon
  5. customrecrystallized three times from ethanol

Sources & evidence

ORD record
ord-e23f1e66128145c49cd6ff71123c2f92
Source dataset
uspto-grants-1979_04
Patent number
US04151180

Linked notes

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