Reaction #64364

Reaction equation

diethyl-aluminum cyanide

NaOH

7,8-dihydro-6,6-dimethyl-7,8-epoxy-6H-pyrano[2,3-f]benzo-2,1,3-oxadiazole

→

8-cyano-6,6-dimethyl-6H-pyrano[2,3-f]benzo-2,1,3-oxadiazole

Solvents

toluene

toluene

Conditions

Workup

1. 1
   Temperaturecooling
2. 2
   workup.STIRRINGby stirring at room temperature for 2 hours
3. 3
   workup.ADDITIONwas added
4. 4
   ExtractionThe mixture was extracted with methylene chloride
5. 5
   Washthe organic layer was washed with water
6. 6
   Otherdried
7. 7
   OtherThe solvent was removed by distillation
8. 8
   Otherthe residue was purified by silica gel column chromatography (developing solution: CH2Cl2)

Procedure

To a mixture of 3.9 g of 7,8-dihydro-6,6-dimethyl-7,8-epoxy-6H-pyrano[2,3-f]benzo-2,1,3-oxadiazole and 80 ml of toluene was added dropwise 90 ml of a 1.0M solution of diethyl-aluminum cyanide in toluene with stirring under ice-cooling, followed by stirring at room temperature for 2 hours. The reaction mixture was poured into ice-water, and 2N NaOH was added thereto. The mixture was extracted with methylene chloride, and the organic layer was washed with water and dried. The solvent was removed by distillation, and the residue was purified by silica gel column chromatography (developing solution: CH2Cl2) to obtain 2.9 g of 8-cyano-6,6-dimethyl-6H-pyrano[2,3-f]benzo-2,1,3-oxadiazole represented by formula shown below.

Source