Pyridin系アミンオキシドの一新脱オキシ反応 (第3報)
4-Nitropyridin-N-oxydとPCl3との反応
1955 年 75 巻 2 号 p. 123-126
詳細
1955 年 75 巻 2 号 p. 123-126
The reaction of 4-nitropyridine 1-oxide and phosphorus trichloride proceeds in the following order: O2N- N→O+PCl3(A)→O2N- N+POCl3(B)→Cl- N+O= N- N
What effect the kind of solvent used and reaction temperature had on the side-reaction (B) was examined and following results were obtained:
1) Ethyl acetate and chloroform are suitable as the reaction solvent and carbon disulfide and dioxane are unsuitable.
2) In general, reaction carried out in the cold resulted in the recovery of the starting material, indicating the necessity of warming at a definite temperature for the completion of the reaction.
3) Heating at a higher temperature or lengthening of the reaction period tends to cause greater occurrence of the (B) reaction. The formation of N-(4′-pyridyl)-4-pyridone is marked in carbon tetrachloride.
Application of aniline hydrochloride or 10% hydrochloric acid to N-(4′-pyridyl)-4-pyridone results in the formation of two moles of pyridine derivatives but the application of 10% sodium hydroxide causes partial cleavage of the pyridine ring. There is no reaction with 28% ammonia water or water.
