Reaktion #165336

Reaktionsgleichung

6-bromo-pyridine-3-carbaldehyde

ethylene glycol

p-toluenesulfonic acid monohydrate

Sodium hydrogencarbonate

→

title compound

Ausbeute 97.0%

2-Bromo-5-[1,3]dioxolan-2-yl-pyridine

Ausbeute 97.0%

Lösungsmittel

toluene

water

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturwas refluxed for 3 hours and 40 minutes under nitrogen atmosphere
2. 2
   Extraktionwas extracted with ethyl acetate
3. 3
   SonstigeThe organic layer was separated
4. 4
   Waschenwashed with saturated aqueous sodium chloride
5. 5
   Trocknendried over anhydrous magnesium sulfate
6. 6
   Filtrationfiltered
7. 7
   EinengenThe filtrate was concentrated under a reduced pressure
8. 8
   Sonstigethe residue was purified by NH silica gel column chromatography (heptane: ethyl acetate=1:1)

Vorschrift

To a toluene (100 mL) solution of 6-bromo-pyridine-3-carbaldehyde (5.0 g, 27 mmol) described in Manufacturing Example 154-1-1 were added ethylene glycol (3.0 mL, 54 mmol) and p-toluenesulfonic acid monohydrate (512 mg, 2.7 mmol), which was refluxed for 3 hours and 40 minutes under nitrogen atmosphere. Sodium hydrogencarbonate and water were added to the reaction mixture, which was extracted with ethyl acetate. The organic layer was separated, washed with saturated aqueous sodium chloride, dried over anhydrous magnesium sulfate, and filtered. The filtrate was concentrated under a reduced pressure, and the residue was purified by NH silica gel column chromatography (heptane: ethyl acetate=1:1) to obtain the title compound (6.0 g, 97%).

Quelle