反应详情

温度

5 °C

To a mixture of 7-methyl-3-phenyl-2H-1,4-benzoxazine (22.5 g, 99.87 mmol) in ethyl ether (300 mL) is added trifluoroacetic acid (7.7 mL, 99.87 mmol). The resulting solution is chilled to 5° C. in an ice bath and n-butyl nitrite (12.26 mL, 99.87 mmol) is added dropwise. The mixture is stirred for 1 h; solids formed during the reaction. The solids are collected by filtration and washed with ether. The filtrates are partitioned between ether and water and the organic layers are washed three times with water (500 mL), dried over magnesium sulfate, and concentrated to dryness. The combined solids gave 23.22 g (97%) of 7-methyl-4-nitroso-3-phenyl-3,4-dihydro-2H-1,4-benzoxazine.

1. customsolids formed during the reaction
2. filtrationThe solids are collected by filtration
3. washwashed with ether
4. customThe filtrates are partitioned between ether and water
5. washthe organic layers are washed three times with water (500 mL)
6. dry with materialdried over magnesium sulfate
7. concentrationconcentrated to dryness