反应详情

温度

140 °C

A suspension of O,N-dimethyl-2-chloropyridine-5-hydroxamic acid (10.0 g, 50 mmol-see Preparation 22(i)), imidazole (4.1 g, 60 mmol) and potassium carbonate (6.9 g, 50 mmol) in N,N-dimethylacetamide (200 ml) was stirred at 140° C. for 24 hours. The mixture was evaporated under reduced pressure and the residue was partitioned between dichloromethane (100 ml) and water (100 ml). The organic phase was washed with water (100 ml) and brine (50 ml) then dried (MgSO4) and evaporated under reduced pressure. The crude product was purified by column chromatography on silica using gradient elution with ethyl acetate/hexane (1:1,1:0). Fractions containing the desired product were combined and evaporated under reduced pressure to give the title compound (8.2 g, 71%) as an orange oil. A sample was triturated with ether to afford a colourless solid, m.p. 69-70° C.

1. customThe mixture was evaporated under reduced pressure
2. customthe residue was partitioned between dichloromethane (100 ml) and water (100 ml)
3. washThe organic phase was washed with water (100 ml) and brine (50 ml)
4. dry with materialthen dried (MgSO4)
5. customevaporated under reduced pressure
6. customThe crude product was purified by column chromatography on silica using gradient elution with ethyl acetate/hexane (1:1,1:0)
7. additionFractions containing the desired product
8. customevaporated under reduced pressure