Reaction #62788

Reaction equation

water

oxalyl chloride

2-(2-Chloro-4-methanesulfonylbenzoyl)-cyclohexane-1,3-dione

dimethylformamide

→

3-chloro-2-(2chloro-4-methanesulfonylbenzoyl)cyclohex-2-enone

Yield 70.1%

Solvents

methylene chloride

Conditions

Workup

1. 1
   workup.STIRRINGThe resulting solution was stirred for 4 hours
2. 2
   Extractionextracted with methylene chloride
3. 3
   WashThe organic layer was washed again with water, saturated K2CO3 solution
4. 4
   Dryingdried with MgSO4
5. 5
   Otherthe solvent evaporated

Procedure

2-(2-Chloro-4-methanesulfonylbenzoyl)-cyclohexane-1,3-dione (9.8 g, 30 millimole) was dissolved in 100 ml methylene chloride and stirred at room temperature. To this solution was added oxalyl chloride (5.7 g, 45 mmol) followed by dimethylformamide (0.5 ml) in portions small enough to control effervescence. The resulting solution was stirred for 4 hours and then poured into water and extracted with methylene chloride. The organic layer was washed again with water, saturated K2CO3 solution and then dried with MgSO4 and the solvent evaporated to yield 3-chloro-2-(2chloro-4-methanesulfonylbenzoyl)cyclohex-2-enone (7.3 g, 70%) as an oil which was used without further purification.

Source