反应详情

A mixture of 2-chloro-1-pyrroline, prepared as in Example 1 using toluene instead of acetonitrile, and 0.8 g of the product aniline of Example 38 in anhydrous toluene was heated at reflux for five hours. Upon cooling the toluene was removed by decanting and the residue was partitioned between water and dichloromethane. The aqueous layer was made alkaline with 50% sodium hydroxide and extracted with dichloromethane. The organic phase was dried over potassium carbonate, filtered, concentrated to an oil. The crude product was purified by low-pressure chromatography on silica gel, using as eluent 74:25:1 dichloromethane/ethanol/concentrated aqueous ammonia. The oily product was dissolved in ethanol and acidified with HCl in isopropyl alcohol. Addition of diethyl ether produced the title compound as the hydrochloride salt, m.p. 367°-370°. Structure assignment was supported by the nmr spectrum and by elemental analysis.

1. temperaturewas heated
2. temperatureat reflux for five hours
3. customwas removed
4. customby decanting
5. customthe residue was partitioned between water and dichloromethane
6. extractionextracted with dichloromethane
7. dry with materialThe organic phase was dried over potassium carbonate
8. filtrationfiltered
9. concentrationconcentrated to an oil
10. customThe crude product was purified by low-pressure chromatography on silica gel
11. dissolutionThe oily product was dissolved in ethanol
12. additionAddition of diethyl ether