Réaction #42571

Équation de réaction

2-triethylstannyloxazole

methyl 3-[(dipropylamino)carbonyl]-5-iodobenzoate

→

methyl 3-[(dipropylamino)carbonyl]-5-(1,3-oxazol-2-yl)benzoate

Rendement 27.8%

Solvants

dimethylformamide

Conditions de réaction

Traitement

1. 1
   Autrepurged with argon
2. 2
   Autrethe reaction mixture was degassed under reduced pressure for 15 min
3. 3
   Autrepurged with argon
4. 4
   TempératureThe reaction mixture was heated
5. 5
   Températureat reflux for 2 d
6. 6
   workup.ADDITIONdiluted with ethyl acetate
7. 7
   Lavagewashed with water (3×50 mL)
8. 8
   Séchagedried (sodium sulfate)
9. 9
   Concentrationconcentrated under reduced pressure
10. 10
    AutrePurification by flash column chromatography (silica, 1:1 ethyl acetate/hexanes)

Mode opératoire

A stirred solution of 2-triethylstannyloxazole (Chem. Mater. 1994, 6, 1023) (1.5 g, 5.5 mmol) and methyl 3-[(dipropylamino)carbonyl]-5-iodobenzoate (1.8 g, 4.6 mmol) in dimethylformamide (12 mL) was degassed under reduced pressure for 15 min and purged with argon. Palladium(0)tetrakis(triphenylphosphine) (158 mg, 0.14 mmol) was added and the reaction mixture was degassed under reduced pressure for 15 min and then purged with argon. The reaction mixture was heated at reflux for 2 d, cooled to room temperature, diluted with ethyl acetate, washed with water (3×50 mL), dried (sodium sulfate), and concentrated under reduced pressure. Purification by flash column chromatography (silica, 1:1 ethyl acetate/hexanes) provided methyl 3-[(dipropylamino)carbonyl]-5-(1,3-oxazol-2-yl)benzoate (423 mg): 1H NMR (300 MHz, CDCl3) δ 8.73 (s, 1H), 8.23 (s, 1H), 8.11 (s, 1H), 7.76 (s, 1H), 7.28 (s, 1H), 3.97 (s, 3H), 3.49 (br s, 2H), 3.18 (br s, 2H), 1.72 (d, J=7 Hz, 2H), 1.55 (d, J=7 Hz, 2H), 1.00 (t, J=7 Hz, 3H), 0.75 (t, J=7 Hz, 3H).

Source