Réaction #742250

Équation de réaction

3-[5-methyl-2-(tetrahydro-pyran-2-yloxy)-phenyl]-acrylic acid ethyl ester

p-toluenesulfonic acid

→

colourless crystals

Rendement 71.0%

(E)-3-(2-Hydroxy-5-methyl-phenyl)-acrylic acid ethyl ester

Rendement 71.0%

Solvants

ethanol

Conditions de réaction

Traitement

1. 1
   ConcentrationThen the reaction mixture was concentrated
2. 2
   workup.ADDITIONthe residue was diluted with ether
3. 3
   Lavagewashed with saturated sodium bicarbonate and brine
4. 4
   Autredried
5. 5
   Autreevaporated to dryness
6. 6
   AutreThe resulting yellow solid was recrystallized

Mode opératoire

A solution of 193.7 g 3-[5-methyl-2-(tetrahydro-pyran-2-yloxy)-phenyl]-acrylic acid ethyl ester (Bunce, R., Moore, J., Org. Prep. Proc., 29(3), 293 (1997)) and 2 g p-toluenesulfonic acid in 2.5 l of ethanol was stirred at room temperature for 24 hours. Then the reaction mixture was concentrated and the residue was diluted with ether, washed with saturated sodium bicarbonate and brine, dried and evaporated to dryness. The resulting yellow solid was recrystallized to yield 97.7 g of colourless crystals.

Source