Reaktion #64343

Reaktionsgleichung

potassium t-butoxide

6-cyano-3,4-dihydro-2,2-dimethyl-2H-1-benzopyran-3-one

phenyl isothio-cyanate

N,N-dimethylformamide

→

N-phenyl-6- cyano-3-hydroxy-2,2-dimethyl-2H-1-benzopyran-4-carbothioamide

Ausbeute 47.9%

Lösungsmittel

acetic acid

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturcooling
2. 2
   Temperaturcooling
3. 3
   Extraktionextracted with diethyl ether
4. 4
   WaschenThe extract was washed with water
5. 5
   Trocknendried over sodium sulfate
6. 6
   Sonstigethe ether layer was removed by distillation
7. 7
   SonstigeThe residue was purified by silica gel column chromatography (developing solution: CH2Cl2)

Vorschrift

To a mixture of 0.5 g of 6-cyano-3,4-dihydro-2,2-dimethyl-2H-1-benzopyran-3-one, 0.37 g of phenyl isothio-cyanate, and 5 ml of dried N,N-dimethylformamide was added 0.31 g of potassium t-butoxide with under ice-cooling, followed by stirring for 5 hours under ice-cooling. Ice-water was added thereto, and the mixture was made acidic with acetic acid and extracted with diethyl ether. The extract was washed with water and dried over sodium sulfate, and the ether layer was removed by distillation. The residue was purified by silica gel column chromatography (developing solution: CH2Cl2) to obtain 0.4 g of N-phenyl-6- cyano-3-hydroxy-2,2-dimethyl-2H-1-benzopyran-4-carbothioamide represented by formula shown below.

Quelle