Réaction #792144

Équation de réaction

HCl

resorcinol

3-pyridin-2-yl-propionic acid sulphuric acid salt

NaOAc

→

final product

Rendement 24.0%

1-(2,4-dihydroxyphenyl)-3-(pyridine-2-yl)propan-1-one

Rendement 24.0%

Solvants

boron trifluoride diethyl etherate

Conditions de réaction

Traitement

1. 1
   workup.WAITto stand for 30 min
2. 2
   Extractionwas extracted with EtOAc (3×50 ml)
3. 3
   LavageThe combined EtOAc layer was washed with water, brine
4. 4
   Séchagedried over Na2SO4
5. 5
   AutreThe residue obtained
6. 6
   Autreafter evaporation of the solvent
7. 7
   Autrewas chromatographed over silica gel column
8. 8
   Autreto give
9. 9
   workup.ADDITIONmixture of products, which
10. 10
    Autrewas then recrystallized in hot MTBE/Hex

Mode opératoire

A mixture of resorcinol (2.2 g, 20 mmol), 3-pyridin-2-yl-propionic acid sulphuric acid salt (5 g, 20 mmol) and 50 ml boron trifluoride diethyl etherate (BF3.Et2O) was stirred at 90 C for 5 hours under N2 (monitored by TLC). The reaction mixture was poured into 10% aqueous NaOAc solution and allowed to stand for 30 min and the solution was neutralized to pH=7 by 1M HCl and was extracted with EtOAc (3×50 ml). The combined EtOAc layer was washed with water, brine and dried over Na2SO4. The residue obtained after evaporation of the solvent was chromatographed over silica gel column using hexane-EtOAc mixture (1:1) as eluent to give mixture of products, which was then recrystallized in hot MTBE/Hex to afford final product (24%) with >97% purity.

Source