Reaktion #7241

Reaktionsgleichung

sodium potassium tartrate

3-n-propoxypicolinic acid n-propyl ester

DIBAL-H

→

3-n-propoxypyridine-2-carboxaldehyde

Ausbeute 113.5%

Lösungsmittel

CH2Cl2

CH2Cl2

CH2Cl2

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.WAITat room temperature for 3 hrs
2. 2
   workup.STIRRINGstirred vigorously for 65 hrs
3. 3
   SonstigeThe phases were separated
4. 4
   Extraktionthe aqueous phase extracted with CH2Cl2 (3×20 mL)
5. 5
   TrocknenThe combined organic phases were dried (Na2SO4)
6. 6
   Einengenconcentrated
7. 7
   Sonstigeto give a yellow oil
8. 8
   workup.STIRRINGThe mixture was stirred for 19 hrs
9. 9
   Filtrationthen filtered through celite
10. 10
    EinengenThe filtrate was concentrated

Vorschrift

To a stirred solution of 3-n-propoxypicolinic acid n-propyl ester (0.1209 g, 0.541 mmol) in dry CH2Cl2 (5 mL) at −78° C. was added DIBAL-H (1.0 M, 2.5 mL, 2.5 mmol). The mixture was stirred at −78° C. for 1 hr, then at room temperature for 3 hrs. The mixture was poured into saturated aqueous sodium potassium tartrate (15 mL), diluted with CH2Cl2 (15 mL) and stirred vigorously for 65 hrs. The phases were separated and the aqueous phase extracted with CH2Cl2 (3×20 mL). The combined organic phases were dried (Na2SO4) and concentrated to give a yellow oil. The yellow oil was dissolved in CH2Cl2 (5 mL) and treated with MnO2 (˜85%, 0.4549 g, 4.45 mmol). The mixture was stirred for 19 hrs then filtered through celite. The filtrate was concentrated to give 0.1014 g of 3-n-propoxypyridine-2-carboxaldehyde as an orange oil. 1H NMR (CDCl3) d 1.09 (t, 3H, J=7.4 Hz), 1.91 (sextet, 2H, J=7.1 Hz), 4.07 (t, 2H, J=6.6 Hz), 7.38–7.47 (m, 2H), 8.39 (dd, 2H, J=4.4, 1.4 Hz), 10.43 (s, 1H).

Quelle