反应详情

To a solution of 3.12 g. of 2-propyl-3,4dichlorophenol in 30 ml. of dry tetrahydrofuran and 30 ml. of dry hexamethylphosphoramide were added 0.72 g. of a 50% sodium hydride dispersion in oil. Two milliliters of 1,5-dibromopentane were then added followed by a catalytic amount of potassium iodide. The reaction was stirred overnight under a nitrogen atmosphere at 60°-70° C. The reaction was then cooled to room temperature, ethyl acetate and water were added, and the solution was evaporated to dryness. Ethyl acetate and water were added to the residue and the layers were separated. The ethyl acetate layer was washed with dilute acid to remove residual hexamethylphosphoramide. The ethyl acetate was then washed with a saturated sodium chloride solution, filtered through sodium sulfate, and evaporated to dryness. The residue was purified by high pressure liquid chromatography to provide 1.6 g. of the desired bromo intermediate. NMR.

1. customthe solution was evaporated to dryness
2. additionEthyl acetate and water were added to the residue
3. customthe layers were separated
4. washThe ethyl acetate layer was washed
5. additionwith dilute acid
6. customto remove residual hexamethylphosphoramide
7. washThe ethyl acetate was then washed with a saturated sodium chloride solution
8. filtrationfiltered through sodium sulfate
9. customevaporated to dryness
10. customThe residue was purified by high pressure liquid chromatography
11. customto provide 1.6 g