Synthesis and Structure of Functionalized Homo Heteracalix[2]arene[2]triazines: Effect of All Heteroatom Bridges on Macrocyclic Conformation

Synthesis of Inherently Chiral Homo-heteracalixaromatics

There is a resurgence of research interest in inherently chiral calixarenes and heteracalixaromatics. However, the examples of macrocyclic ring-expanded homocalixarenes and heterocalixaromatics of inherent chirality are not known. Here we report an efficient method to construct inherently chiral N2,O2-linked homo-heteracalixaromatics from reductive amination reactions between bis-aldehydes and aliphatic diamines. Examples of post-macrocyclization derivatization were also demonstrated. Enantiomers were obtained from resolution and did not undergo racemization at an elevated temperature. This study provides a new strategy to design novel and functional inherently chiral macrocycles that have potential applications in supramolecular chemistry.

FeO(OH)@C-Catalyzed Selective Hydrazine Substitution of p-Nitro-Aryl Fluorides and their Application for the Synthesis of Phthalazinones

An efficient hydrazine substitution of p-nitro-aryl fluorides with hydrazine hydrates catalyzed by FeO(OH)@C nanoparticles is described. This hydrazine substitutions of p-nitro-aryl fluorides bearing electron-withdrawing groups proceeded efficiently with high yield and selectivity. Similarly, hydrogenations of p-nitro-aryl fluorides containing electron-donating groups also smoothly proceeded under mild conditions. Furthermore, with these prepared aryl hydrazines, some phthalazinones, interesting as potential structures for pharmaceuticals, have successfully been synthesized in high yields.