Reaction #527561

Reaction equation

diethyl phenylsulphonylmethylphosphonate

methyl benzoylformate

lithium bis(trimethylsilyl)amide

lithium bis(trimethylsilyl)amide

ethyl acetate hexane

ethyl acetate hexane

ethyl acetate hexane

tetrahydrofuran

→

2-phenyl-3-sulfonylphenyl-propenoic acid, methyl ester

Conditions

Workup

1. 1
   TemperatureCool in an ice-bath
2. 2
   workup.STIRRINGstir for 2 hours
3. 3
   OtherPartition between water and ethyl acetate
4. 4
   ExtractionExtract the aqueous layer with ethyl acetate
5. 5
   Dryingdry over magnesium sulfate
6. 6
   Otherevaporate in vacuo
7. 7
   Otherto give an oil
8. 8
   OtherTriturate with cyclohexane
9. 9
   Otherto give a solid
10. 10
    OtherEvaporation of the product
11. 11
    workup.ADDITIONcontaining fractions
12. 12
    Othergive a solid
13. 13
    OtherRecrystallize
14. 14
    Otherform ethyl acetate/hexane

Procedure

Combine diethyl phenylsulphonylmethylphosphonate (T. A. Blumenkopf Synth. Commun. 26, 139-147, (1986)) (117.0 g, 400 mmol) and tetrahydrofuran (500 mL). Cool in an ice-bath. Add lithium bis(trimethylsilyl)amide (480 mL, 1M in tetrahydrofuran, 480 mmol). Stir for 30 minutes after the addition of lithium bis(trimethylsilyl)amide, then add methyl benzoylformate (72.0 g, 439 mmol). Warm to ambient temperature and stir for 2 hours. Partition between water and ethyl acetate. Extract the aqueous layer with ethyl acetate. Combine the organic layers, dry over magnesium sulfate and evaporate in vacuo to give an oil. Triturate with cyclohexane to give a solid. Chromatograph the solid on silica gel eluting sequentially with 10% ethyl acetate/hexane, 15% ethyl acetate/hexane, and 33% ethyl acetate/hexane. Evaporation of the product containing fractions give a solid. Recrystallize form ethyl acetate/hexane to give 2-phenyl-3-sulfonylphenyl-propenoic acid, methyl ester as a solid. Elem. Anal calculated for C16H14O4S: C, 63.56; H, 4.67. Found: C, 63.25; H, 4.70.

Source