Reacción #42571

Ecuación de reacción

2-triethylstannyloxazole

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

→

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

Rendimiento 27.8%

Disolventes

dimethylformamide

Condiciones de reacción

Tratamiento posterior

1. 1
   Otropurged with argon
2. 2
   Otrothe reaction mixture was degassed under reduced pressure for 15 min
3. 3
   Otropurged with argon
4. 4
   TemperaturaThe reaction mixture was heated
5. 5
   Temperaturaat reflux for 2 d
6. 6
   workup.ADDITIONdiluted with ethyl acetate
7. 7
   Lavadowashed with water (3×50 mL)
8. 8
   Secadodried (sodium sulfate)
9. 9
   Concentraciónconcentrated under reduced pressure
10. 10
    OtroPurification by flash column chromatography (silica, 1:1 ethyl acetate/hexanes)

Procedimiento

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).

Fuente