反应详情

A mixture of 6-nitro-2,3-dihydrobenz-1,4-oxazine (0.45 g.), methyl 4-bromomethyl-3-methoxybenzoate (B) (0.65 g.), anhydrous potassium carbonate (0.35 g.), sodium iodide (0.38 g.) and acetone (25 ml.) was stirred and heated under reflux for 48 hours, under an atmosphere of nitrogen. The cooled reaction mixture was separated by filtration. The residue was washed with acetone, and the filtrate and washings were evaporated. The resulting solid was dissolved in dichloromethane and residual solid removed by filtration. The filtrate was evaporated. The product was purified by flash chromatography on silica gel (3 cm. diameter column), eluting with 1:10 v/v ethyl acetate: toluene, to give methyl 3-methoxy-4-(6-nitro-2,3-dihydrobenz-1,4-oxazin-4-ylmethyl)benzoate (G) (0.75 g., 84%), m.p. 130°-132° C.; NMR (80 MHz, CDCl3): 3.0(t,2H, OCH2.CH2N), 3.8(s,3H, OCH3), 3.95(s,3H, OCH3), 4.3(t, 2H, OCH2.CH2N), 4.5(s,2H, CH2.Ar), 6.8(d,1H), 7.5(m, 5H).

1. temperatureheated
2. temperatureunder reflux for 48 hours, under an atmosphere of nitrogen
3. customThe cooled reaction mixture
4. customwas separated by filtration
5. washThe residue was washed with acetone
6. customthe filtrate and washings were evaporated
7. dissolutionThe resulting solid was dissolved in dichloromethane
8. customresidual solid removed by filtration
9. customThe filtrate was evaporated
10. customThe product was purified by flash chromatography on silica gel (3 cm. diameter column)
11. washeluting with 1:10 v/v ethyl acetate