Reacción #534191

Ecuación de reacción

1-(5,7-diiodo-benzothiazol-2-yl)-3-ethyl-urea

pyridine 3-boronic acid

K3PO4

→

1-Ethyl-3-(5-iodo-7-pyridin-3-yl-benzothiazol-2-yl)-urea

Disolventes

DMF

Condiciones de reacción

Tratamiento posterior

1. 1
   OtroThe reaction mixture was degassed for half an hour
2. 2
   OtroThe reaction mixture was again degassed for half an hour
3. 3
   workup.DISTILLATIONDMF was distilled off
4. 4
   workup.ADDITIONadded water
5. 5
   Extracciónextracted with ethyl acetate (×3)
6. 6
   SecadoThe combined organic layer was dried over anhydrous Na2SO4
7. 7
   Otroevaporated to dryness under reduced pressure
8. 8
   OtroThe residue was purified by chromatography on silica (230-400 M)

Procedimiento

To a solution of 1-(5,7-diiodo-benzothiazol-2-yl)-3-ethyl-urea (0.20 g, 0.42 mmol) in DMF (5 mL) was added pyridine 3-boronic acid (0.076 g, 0.63 mmol) and K3PO4 (0.133 g, 0.63 mmol) under nitrogen atmosphere at room temperature. The reaction mixture was degassed for half an hour followed by the addition of bis(triphenylphosphine)palladium(II) dichloride (0.0044 g, 0.063 mmol). The reaction mixture was again degassed for half an hour and then heated at 120° C. for 1 h under nitrogen atmosphere. DMF was distilled off, added water and extracted with ethyl acetate (×3). The combined organic layer was dried over anhydrous Na2SO4, and evaporated to dryness under reduced pressure. The residue was purified by chromatography on silica (230-400 M) using DCM/Methanol (99:1) to provide 1-Ethyl-3-(5-iodo-7-pyridin-3-yl-benzothiazol-2-yl)-urea as an off white solid (0.025 g, 14%) and DCM/Methanol (98:2) to provide 1-Ethyl-3-(7-iodo-5-pyridin-3-yl-benzothiazol-2-yl)-urea as an off white solid (0.025 g, 14%).

Fuente