Reaktion #819577

Reaktionsgleichung

tributyl(1-ethoxyvinyl)tin

methyl 2,6-dichloroisonicotinate

toluene

→

title compound

2-Acetyl-6-chloro-isonicotinic acid methyl ester

Lösungsmittel

diethyl ether

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.ADDITIONfilled
2. 2
   Sonstigesealed vessel
3. 3
   SonstigeFlush the reactants with nitrogen again
4. 4
   TemperaturCool
5. 5
   Sonstigethe reaction to room temperature
6. 6
   Filtrationfilter through a filtering agent
7. 7
   EinengenConcentrate
8. 8
   workup.ADDITIONdilute the residue with THF (10 mL)
9. 9
   workup.ADDITIONAdd dropwise 5 N HCl (5 mL)
10. 10
    EinengenConcentrate
11. 11
    Extraktionextract the organic material by diethyl ether
12. 12
    Sonstigepartitioning with water
13. 13
    TrocknenDry (magnesium sulfate)
14. 14
    Einengenconcentrate
15. 15
    Sonstigepurify
16. 16
    Waschen(silica gel chromatography, eluting with 0:100 to 10:90 ethyl acetate:hexanes)

Vorschrift

Add methyl 2,6-dichloroisonicotinate (3.0 g, 15.0 mmol), trans-dichlorobis(triphenylphosphine)palladium (II) (105 mg, 0.15 mmol) and toluene (10 mL) in a previously nitrogen filled sealed vessel. Flush the reactants with nitrogen again. Add tributyl(1-ethoxyvinyl)tin (5.57 mL, 16.5 mmol) under nitrogen and heat the sealed mixture at 100° C. overnight with vigorous stirring. Cool the reaction to room temperature, dilute with diethyl ether and filter through a filtering agent. Concentrate to near dryness and dilute the residue with THF (10 mL). Add dropwise 5 N HCl (5 mL) and stir the mixture overnight. Concentrate to near dryness and extract the organic material by diethyl ether, partitioning with water. Dry (magnesium sulfate), concentrate and purify (silica gel chromatography, eluting with 0:100 to 10:90 ethyl acetate:hexanes) to give the title compound as a solid over two steps (47%).

Quelle