Reaction #94744

Reaction equation

1-(3',4'-dimethoxyphenyl)-7-phenyl-2-nitro-5-heptanone

p-toluenesulfonic acid

ethylene glycol

→

oil

1-(3',4'-dimethoxyphenyl)-7-phenyl-2-nitro-5-heptanone ethylene ketal

Solvents

cyclohexane

Conditions

Workup

1. 1
   Otherflask equipped with a Dean Stark trap
2. 2
   Temperatureto reflux overnight
3. 3
   Concentrationconcentrated in vacuo
4. 4
   workup.ADDITIONDil NaHCO3 solution was added to the residue
5. 5
   Extractionextracted with ethyl acetate
6. 6
   Dryingdried over anh. MgSO4
7. 7
   Filtrationfiltered
8. 8
   Concentrationconcentrated under reduced pressure

Procedure

Into a 1 l r.b. flask equipped with a Dean Stark trap was placed 46.4 g (0.12 m) of 1-(3',4'-dimethoxyphenyl)-7-phenyl-2-nitro-5-heptanone, 1.5 g p-toluenesulfonic acid, 50 mL of ethylene glycol and 300 mL of cyclohexane. The mixture was allowed to reflux overnight, then concentrated in vacuo. Dil NaHCO3 solution was added to the residue and extracted with ethyl acetate. The organic layer was backwashed with water, dried over anh. MgSO4, filtered and concentrated under reduced pressure to give 45.3 g of an oil which solidified on drying at room temperature under vacuum.

Source