Reaktion #9736

Reaktionsgleichung

sodium chlorite

4-[4-(trifluoromethyl)phenyl]thiophene-2-carbaldehyde

intermediate 37

4-[4-(trifluoromethyl)phenyl]thiophene-2-carbaldehyde

2-methyl-2-butene

sodium dihydrogen phosphate

→

title compound

4-[4-(trifluoromethyl)phenyl]thiophene-2-carboxylic acid

Lösungsmittel

water

t-butanol

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.ADDITIONTo this was added drop-wise
2. 2
   workup.ADDITIONAfter the addition
3. 3
   EinengenThe solution was then concentrated
4. 4
   Sonstigepartitioned between water and ethyl acetate
5. 5
   WaschenThe aqueous layer was washed with a second ethyl acetate portion
6. 6
   Waschenwashed with brine
7. 7
   Trocknendried (MgSO4)
8. 8
   SonstigeThe solution was then absorbed onto silica
9. 9
   WaschenThe product was eluted with neat ethyl acetate

Vorschrift

A solution of 4-[4-(trifluoromethyl)phenyl]thiophene-2-carbaldehyde (intermediate 37, 1.23 g), t-butanol (20 ml) and 2-methyl-2-butene (10 ml) was cooled to 0° C. To this was added drop-wise, a solution of sodium chlorite (3.8 g) and sodium dihydrogen phosphate (4.03 g) in water (15 ml). After the addition was complete, the mixture was allowed to warm to room temperature and was stirred for 4 hours. The solution was then concentrated and partitioned between water and ethyl acetate. The aqueous layer was washed with a second ethyl acetate portion and the organic liquors were combined, washed with brine, then dried (MgSO4). The solution was then absorbed onto silica and loaded onto a SPE (Si) cartridge. The product was eluted with neat ethyl acetate to afford the title compound as a white solid.

Quelle