反应详情

To a suspension of NaH 60% dispersion in oil (97 mg, 0.0023 mol) in 2 mL of anhydrous THF at 0° C. was added 2-bromo-5-nitroaniline (500 mg, 0.0023 mol) in 2 mL of THF dropwise, the temperature was raised to rt to complete deprotonation then lowered to 0° C. 3-bromo-2-methylpropene (232 mL, 0.0023 mol) was added very slowly and the reaction mixture was stirred at 0° C. for 3 h then neutralized with water (5 mL). The mixture was extracted with ethyl acetate (2×10 mL), dried (Na2SO4) and concentrated in vacuo to an oil that was subjected to flash column chromatography (silica gel, hexanes/ethyl acetate, 8:2) to give 200 mg (32%) of 2-bromo-N-(2-methyl-2-propenyl)-5-nitroaniline (structure 55A of Scheme XLVII, where R1 =methyl, R2 =H). Data for 2-bromo-N-(2-methyl-2-propenyl)-5-nitroaniline: 1H NMR (400 MHz, CDCl3) 7.55 (d, J=8.5, 1H), 7.40 (dd, J=8.5, 2.8, 1H), 7.39 (d, J=2.8, 1H), 4.96 (s, 2H), 4.95 (bs, 1H), 3.82 (d, J=5.9, 2H), 1.81 (s, 3H).

1. customthen lowered to 0° C
2. extractionThe mixture was extracted with ethyl acetate (2×10 mL)
3. dry with materialdried (Na2SO4)
4. concentrationconcentrated in vacuo to an oil that