Reaktion #579404

Reaktionsgleichung

2-phenyl-3-o-tolyl-thiophene

methacrylic acid

Eaton's reagent

→

product ( 3 )

Ausbeute 96.4%

5-methyl-2-phenyl-3-o-tolyl-4,5-dihydrocyclopenta[b]thiophen-6-one

Ausbeute 96.4%

Lösungsmittel

dichloromethane

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.ADDITIONOn completion of the addition
2. 2
   workup.ADDITIONgradually added
3. 3
   Sonstigeto crushed ice
4. 4
   workup.DISSOLUTIONto dissolve the reaction product
5. 5
   SonstigeThe organic phase was removed
6. 6
   Waschenwashed with a saturated aqueous solution of sodium hydrogencarbonate
7. 7
   Trocknendried over magnesium sulfate
8. 8
   SonstigeAfter removing the solvent

Vorschrift

A mixture of 31.8 g of 2-phenyl-3-o-tolyl-thiophene (0.127 mol) and 13.3 ml of methacrylic acid (0.157 mol) was added within 30 minutes at about 80° C. to 500 ml of Eaton's reagent. On completion of the addition, the reaction mixture was stirred for a further 5 minutes and then gradually added to crushed ice. 300 ml of dichloromethane were added to dissolve the reaction product. The organic phase was removed, washed with a saturated aqueous solution of sodium hydrogencarbonate and dried over magnesium sulfate. After removing the solvent, 39 g of product (3) were obtained which, according to GC-MS, constituted a single, isomer and had a purity of 95%.

Quelle