反応 #7241

反応方程式

sodium potassium tartrate

3-n-propoxypicolinic acid n-propyl ester

DIBAL-H

→

3-n-propoxypyridine-2-carboxaldehyde

収率 113.5%

溶媒

CH2Cl2

CH2Cl2

CH2Cl2

反応条件

後処理

1. 1
   workup.WAITat room temperature for 3 hrs
2. 2
   workup.STIRRINGstirred vigorously for 65 hrs
3. 3
   その他The phases were separated
4. 4
   抽出the aqueous phase extracted with CH2Cl2 (3×20 mL)
5. 5
   乾燥The combined organic phases were dried (Na2SO4)
6. 6
   濃縮concentrated
7. 7
   その他to give a yellow oil
8. 8
   workup.STIRRINGThe mixture was stirred for 19 hrs
9. 9
   ろ過then filtered through celite
10. 10
    濃縮The filtrate was concentrated

実験手順

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).

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