AbstractIt has been established that the recyclization of 2-aryl-4H-chromen-4-imines under the influence of thiosemicarbazide as N-dinucleophile is completed by the formation of 3-aryl-5-(o-hydroxyaryl)-1H-pyrazole-1-carbothioamides by the 5-exo-trig-cyclization mechanism. Aromatic acid hydrazides (isonicotinic, benzoic, salicylic, and 4-methoxybenzoic) enter into a similar reaction with the participation
摘要已经确定的是2-芳基-4-的再成环ħ
亚胺-苯并
吡喃-4-
氨基
硫脲如N-双亲核试剂的影响下由3-芳基-5-(的形成完成Ò -hydroxyaryl)-1 ħ -
吡唑-1- carbothioamides由5-外型- TRIG -cyclization机制。
芳香酸酰
肼(异
烟碱,
苯甲酸,
水杨酸和4-
甲氧基苯甲酸)在过量的
哌啶的参与下进行类似的反应,形成1 H-
吡唑-5-基
酚。 图形摘要