反应详情

1.78 g (6.4 mmoles) of 3,5-di-tert-butyl-4-hydroxycinnamic acid, 0.99 g (6.4 mmoles) of 4-amino-2-nitrophenol, previously diluted in 10 ml of DMF, 0.86 g (6.4 mmoles) of hydroxybenzotriazol and 1.32 g (6.4 mmoles) of dicyclohexylcarbodiimide are introduced into a 50 ml flask containing 10 ml of THF. The reaction medium is agitated for 15 hours at ambient temperature, the precipitate which appears is filtered and rinsed with ethyl acetate. After concentration of the solution under reduced pressure, the residue is diluted in 20 ml of ethyl acetate and the insoluble part is filtered again. The filtrate is washed with 20 ml of a saturated solution of sodium carbonate followed by 20 ml of water and 20 ml of a saturated solution of sodium chloride. After drying over sodium sulphate, the organic solution is filtered and concentrated to dryness under reduced pressure. The residue is purified on a silica column (eluant: heptane/ethyl acetate: 8/2). The pure fractions are collected and concentrated under vacuum to produce 1.95 g (47%) of the expected compound in the form of a yellow-orange powder. Melting point: 231-232° C.

1. filtrationthe precipitate which appears is filtered
2. washrinsed with ethyl acetate
3. additionAfter concentration of the solution under reduced pressure, the residue is diluted in 20 ml of ethyl acetate
4. filtrationthe insoluble part is filtered again
5. washThe filtrate is washed with 20 ml of a saturated solution of sodium carbonate
6. dry with materialAfter drying over sodium sulphate
7. filtrationthe organic solution is filtered
8. concentrationconcentrated to dryness under reduced pressure
9. customThe residue is purified on a silica column (eluant: heptane/ethyl acetate: 8/2)
10. customThe pure fractions are collected
11. concentrationconcentrated under vacuum