反应详情

To a solution of benzene-1,4-diamine (5.0 g) in NMP (30 ml) was added dropwise, over 0.5 h, a solution of 2-chlorobenzo[d]oxazole (6.03 g) in NMP (50 ml). After the addition was complete, the mixture was stirred at ambient temperature for 1 h. After this time, the reaction mixture was diluted with water (200 mL) and extracted with ethyl acetate (3×200 mL). The combined organic extracts were washed with brine (150 ml), dried (Na2SO4) and filtered. The filtrate was concentrated under reduced pressure. The residue obtained was purified by chromatography (silica, methylene chloride to 1:19 methanol/methylene chloride) to afford N-(1,3-benzoxazol-2-yl)benzene-1,4-diamine (9.20 g) as an off-white solid.

1. additionAfter the addition
2. extractionextracted with ethyl acetate (3×200 mL)
3. washThe combined organic extracts were washed with brine (150 ml)
4. dry with materialdried (Na2SO4)
5. filtrationfiltered
6. concentrationThe filtrate was concentrated under reduced pressure
7. customThe residue obtained
8. customwas purified by chromatography (silica, methylene chloride to 1:19 methanol/methylene chloride)