反应详情

As shown in step 6-iii of Scheme 6, to a solution of 2-amino-3-nitrophenol (5.00 g, 32.4 mmol) in dioxane (50 mL) was added bromine (6.22 g, 2.01 mL, 38.9 mmol). The mixture was stirred for 2 hours and a precipitate formed, which was collected and washed with dioxane and ether. The resulting yellow solid treated with a saturated NaHCO3 solution, which was extracted with EtOAc (3×). The combined organics were dried over Na2SO4, filtered, and concentrated under reduced pressure to yield 2-amino-5-bromo-3-nitrophenol (compound 1015) as a brown solid. This material was carried on as is in subsequent reactions without further purification.

1. customa precipitate formed
2. customwhich was collected
3. washwashed with dioxane and ether
4. additionThe resulting yellow solid treated with a saturated NaHCO3 solution, which
5. extractionwas extracted with EtOAc (3×)
6. dry with materialThe combined organics were dried over Na2SO4
7. filtrationfiltered
8. concentrationconcentrated under reduced pressure