N,N′-Disubstituted phenylpropiolamidines were synthesized from phenylacetylene and carbodiimides. They were inert toward nucleophiles in a neutral or basic medium, but reactive in an acidic one. They reacted in the presence of hydrogen chloride with hydroxylamine, hydrazine, and arylhydrazines to give 5-N-substituted amino-3-phenylisoxazoles, 5-N-substituted amino-3-phenylpyrazole and 5-N-substituted amino-1-aryl-3-phenylpyrazoles, respectively, by nucleophilic addition followed by cyclization. The reaction mechanism is discussed on the basis of the structures of these heterocyclic compounds.
由
苯乙炔和碳二
亚胺合成N,N'-二取代的苯基丙酰胺。它们在中性或碱性介质中对亲核试剂呈惰性,但在酸性介质中具有反应性。他们在
氯化氢存在下与
羟胺、
肼和芳基
肼反应,得到5-N-取代的
氨基-
3-苯基异恶唑、5-N-取代的
氨基-
3-苯基吡唑和5-N-取代的
氨基-1-芳基-分别通过亲核加成然后环化得到
3-苯基吡唑。根据这些
杂环化合物的结构讨论了反应机理。