反应详情

To a solution 41 (800 mg, 2.59 mmol) in DMF (20 mL) at room temperature were added 1-(3-Dimethylaminopropyl)-3-ethyl-carbodiimide hydrochloride (EDC, 593 mg, 3.12 mmol), and 1-Hydroxybenzotriazole hydrate (HOBT, 524 mg, 3.89 mmol). The mixture was stirred 20 min. at room temperature then NH2OTHP (455 mg, 3.89 mmol) was added. The resulting mixture was heated at 50° C. for 24 h then the DMF solvent was evaporated under reduced pressure and the residue was dissolved in CH2Cl2, washed with a saturated aqueous solution of NaHCO3. The combined organic extracts were dried over (MgSO4) then evaporated. The crude compound was purified by flash chromatography using Hexane/acetone (7:3) as solvent mixture. The residue was then dissolved in MeOH (30 mL) then 10-camphorsulfonic acid (CSA, 300 mg, 1.30 mmol) was added. The mixture was stirred 2 h at 50° C. then the solvents were condensed under reduced pressure at room temperature to avoid thermal decomposition. The crude was purified by flash chromatography using CH2Cl2/MeOH (9:1) as solvent mixture giving the title compound 42 (115 mg, 13%) as a yellowish solid.

1. temperatureThe resulting mixture was heated at 50° C. for 24 h
2. customthe DMF solvent was evaporated under reduced pressure
3. dissolutionthe residue was dissolved in CH2Cl2
4. washwashed with a saturated aqueous solution of NaHCO3
5. dry with materialThe combined organic extracts were dried over (MgSO4)
6. customthen evaporated
7. customThe crude compound was purified by flash chromatography
8. dissolutionThe residue was then dissolved in MeOH (30 mL)
9. stirringThe mixture was stirred 2 h at 50° C.
10. customcondensed under reduced pressure at room temperature
11. customThe crude was purified by flash chromatography